JP2001001899A - On-vehicle receiver for train control signal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate a change of frequency selecting characteristic and demodulation system and facilitate simplification and miniaturization of a device in an on-vehicle receiver receiving a train control signal based on a carrier wave frequency predetermined for each railway interval and judging the signal produced according to the received signal. SOLUTION: An analog signal received by a receiver 8 is limited with respect to band through a low pass filter 9, converted into a discrete sequence by a quantized converter 10, and stored in a storage device 11. A transfer function having frequency selecting characteristics is stored in the storage device 11. When the transfer function is executed for the discrete sequence using a multiplier 12 and an adder 13, a controller 15 calculates the sequence having frequency selection and modulated wave extracted, and outputs a signal production judgment according to a calculated modulated wave sequence from an output device 16 to a control device 17. An input/output device 18 can perform the input for display and change of various types of coefficients for transfer functions stored in a storage device 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a train control signal on-vehicle receiver for receiving a train control signal transmitted from an automatic train control device on the ground and determining time-varying speed control information.

[0002]

2. Description of the Related Art FIG.
FIG. 1 is a schematic configuration diagram of a conventional on-vehicle receiver disclosed in Japanese Unexamined Patent Publication (Kokai) No. H10-15095. In the figure, 1 is an antenna (receiver), 2a is the band filter 2 for passing the carrier of the carrier frequency fc ₁
a ₁ , an amplifier 2a ₂ , and a detector 2a ₃ , a receiving circuit including a bandpass filter 2b ₁ for passing a carrier having a carrier frequency fc ₂ , an amplifier 2b ₂ , and a detector 2b ₃ ; 2a and 2b are antennas 1
Are connected in parallel. 3 is a coupling circuit, and 4 is an A / D conversion circuit. Reference numeral 5 denotes an FFT (Fast Fourier Transform) analyzer that classifies the input digital signal for each frequency, and 6 denotes a signal processor that determines a train control signal.
7 is a lower priority contact circuit.

In the above-mentioned conventional on-vehicle receiver,
For example, the train control signal transmitted from the ground side to the car side is fs
When it is _1, the train control signal fs ₁ carrier fc ₁ or fc ₂ modulated with the is transmitted to the vehicle upper side. At this time, different frequency signals in adjacent track closed sections and external noise are mixed. The transmitted signal is received by the antenna 1 (for example, the waveform (a) in FIG. 1),
After passing through one of the band-pass filter 2a ₁ or band filter 2b _1, after being adjusted to a suitable signal level, respectively, by amplifiers 2a _2, 2b _2, it is demodulated to the modulation wave by detector 2a _3, 2b _3. The demodulated signal (for example, FIG. 1
(B) is converted into a digital signal (for example, waveform (c) in FIG. 1) by an A / D conversion circuit 4 via a coupling circuit 3, and is separated for each frequency by an FFT frequency analysis by an FFT analyzer 5. (Graph (d) in FIG. 1). Then, the separated signals for each frequency are used as train control signal data (fs ₁ , fs ₂ ,..., F) stored in the signal processor 6 in advance.
s _n ) is compared to determine which signal is present (speed control information). In the graph (d) of FIG. 1, is determined to be a leak signal from an adjacent blockage section or external noise. The calculated signal indication is output from the lower priority contact circuit 7.

[0004]

In the above-mentioned conventional on-vehicle receiver, a plurality of band-pass filters constituted by analog circuits are used to extract carriers having respective frequencies from a plurality of types of received carriers. It is necessary to provide 2a ₁ and 2b ₁ in the preceding stage, and there is a problem that the device is large and complicated. In addition, in the case of a section in which a train control signal is configured by a combination of control signals with different carrier frequencies, a plurality of the above configurations must be prepared in parallel, and the apparatus tends to be larger and more complicated. . Further, when the frequency selection characteristics and the demodulation method of the bandpass filters 2a ₁ and 2b ₁ need to be changed, there is a problem that it is difficult to change the circuit constant or the range of change is limited. Furthermore, the frequency analysis in the FFT analyzer 5 requires a large calculation scale according to the frequency bandwidth to be measured, and is disadvantageous in terms of real-time performance. If the modulated wave is a square wave, the modulated wave components around the band centered on the carrier frequency are mixed, so that interference occurs near the boundary of the closed section, or a combination of multiple control signals with different carrier frequencies is used. In the case of a train control signal to be performed, there is a problem that signal determination becomes difficult.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and a first object of the invention is to provide a train control signal on-vehicle receiver capable of simplifying and miniaturizing a device. It is. A second object of the present invention is to provide a train control signal on-vehicle receiver that can easily change the frequency selection characteristics and the demodulation method and has high versatility and maintainability.

[0006]

SUMMARY OF THE INVENTION A train control signal on-vehicle receiver according to the present invention comprises band limiting means for limiting high-frequency components of a signal received by an on-vehicle receiving means which are higher than a predetermined frequency. A conversion unit that quantizes the analog signal whose frequency component is limited by the limiting unit into a discrete numerical sequence, performs a numerical operation on the discrete numerical sequence based on a transfer function having a frequency selection characteristic for each carrier frequency, First arithmetic means for calculating a first sequence of numerical values by extracting a signal component having a modulation wave frequency band around a carrier wave frequency;
A second calculating means for performing a numerical operation on the first numerical sequence based on a transfer function having a low-pass characteristic to calculate a second numerical sequence in which a signal component having a modulated wave frequency band is extracted; A third numerical sequence obtained by performing a numerical operation on the second numerical sequence based on a transfer function having a frequency selection characteristic for each train control signal and separating the signals for each modulated wave frequency corresponding to the train control signal Calculating means for calculating the third numerical sequence, validity determining means for determining whether the third numerical sequence satisfies a predetermined condition, and a train corresponding to the third numerical sequence determined to be valid There is provided a presentation determination means for performing a presentation determination according to a control signal.

[0007] The validity judging means determines that the third numerical sequence is valid if the effective value of the third numerical sequence is equal to or higher than a minimum operation level predetermined in a train control signal corresponding to the third numerical sequence. It is to judge.

When the validity judging means judges that the plurality of third numerical sequences are valid, the presenting judging device compares the operation level between the train control signals corresponding to these numerical sequences or determines the superiority. This is to determine the signal indication.

In addition, when there are a plurality of types of carrier frequencies predetermined for each track section and a plurality of train control signals are received using the plurality of types of carrier frequencies, the first to third types are used.
, The validity of the third numerical sequence extracted by performing the numerical operation of (i) is determined, and the present determination unit determines the signal present by a combination of a plurality of train control signals corresponding to the plurality of third numerical sequences determined to be valid. Is determined.

In addition, the first arithmetic means, the second arithmetic means,
And storage means for storing each transfer function used in the third calculation means.

[0011] The apparatus further comprises coefficient value changing means for changing each coefficient value of the transfer function stored in the storage means.

Further, the first operation, the second operation and the third operation
Is used as a non-recursive transfer function.

The first operation, the second operation, and the third operation
Is used as a series low-order transfer function.

The first operation, the second operation and the third operation
Is used as a parallel low-order transfer function.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 shows a train control signal on-vehicle receiver according to an embodiment of the present invention. Reference numeral 8 denotes a receiving means which is installed at a lower part of a vehicle body and receives a train control signal by electromagnetic coupling with a ground side. Electrical appliances,
Reference numeral 9 denotes a low-pass filter that limits high-frequency components equal to or higher than a predetermined frequency. This is because, in a numerical operation performed after quantization, signals up to half of the quantization frequency can be correctly processed, but errors occur in numerical operations for frequency signals exceeding half of the quantization frequency. Therefore, it is provided to remove high-frequency components that may cause the trouble. For example, if the carrier frequency to be received is 15 KHz, taking into account margins such as errors, for example, signals up to 20 KHz can be handled without any problem.
The quantization is set to be doubled at a frequency of 40 KHz. In this case, the low-pass filter 9 limits high-frequency components of 20 KHz or more, which is half of the quantization frequency of 40 KHz. Reference numeral 10 denotes a quantizer for quantizing an analog signal passing through the low-pass filter 9 into a discrete numerical sequence, 11 denotes a numerical sequence quantized by the quantizer 10,
This is a storage device that stores a transfer function used for numerical calculation, a calculation result, and the like. Reference numeral 12 denotes a multiplier for multiplying numerical values, and reference numeral 13 denotes an adder for adding numerical values. 14 is interposed between the storage unit 11 and the quantization converter 10, the multiplier 12, and the adder 13, and based on the designation of a selection signal output by the controller 15 described later to select a path, Quantization converter 10,
A switch that outputs a numerical value from the adder 13 to a specified position in the storage device 11 and outputs a numerical value from the specified position in the storage device 11 to the multiplier 12 and the adder 13. Fifteen
Performs a signal presentation determination according to the received train control signal by performing a numerical operation on the discrete numerical sequence stored in the storage device 11 based on various transfer functions also stored in the storage device 11. It is a controller. Reference numeral 16 denotes an output device for presenting and outputting at each time of reception based on the judgment of the controller 15, and 17 denotes a braking device to be controlled. Reference numeral 18 denotes an input / output device connected to the controller 15 for displaying or changing coefficient values of various transfer functions stored in the storage device 11.

In the on-vehicle train control signal receiver having the above-described structure, the signal received by the power receiver 8 at a constant period is filtered by a low-pass filter 9 to remove unnecessary high-frequency components. Thus, the orbital section is quantized as a discrete numerical sequence in which a modulated wave frequency band is secured around a predetermined carrier frequency. The discrete numerical sequence is arranged in a continuous storage location in the storage device 11 via the switch 14 according to a time sequence. However, since the number of arrangements in the storage unit 11 is finite, an appropriate number of arrangements is determined, and a cyclic operation is repeated such that when the arrangement from the first place to the last place in the arrangement order is filled with the discrete numerical sequence, the data is returned to the first place and stored. . This is referred to as a numerical sequence x [k]. Controller 15
Performs a first numerical operation on this numerical sequence x [k] based on a transfer function having a frequency selection characteristic for each carrier frequency, and then performs a second numerical operation based on a transfer function having a low-pass characteristic. A third numerical operation based on a transfer function having a frequency selection characteristic for each train control signal is performed.

The transfer function having an order n of the band-pass characteristic by using a general differential operator s, H (s) = 1 / (q [0] · s n + q [1] · s n-1 + ·· .. + Q [n]) (1) When the variable s is converted into a z variable which is a time delay element of a discrete system, from equation (1), H (z) = Σb [k] · z ^(−k) / (1−Σa [j] · z ^{(− j)} ) (2) k = 0, 1, 2,..., K j = 1, 2,..., J; K and J are integers. The above equation (2) is converted into an input numerical sequence x [k] and an output numerical sequence y [n].
Y [n] = Σa [j] · y [nj] + Σb [k] · x [nk] (3) k = 0, 1, 2,..., K j = 1,2, ..., J; K and J are integers. Note that the coefficient sequences a [j] and b [k] are constants determined in advance by the passing filter characteristic, and are stored in a predetermined location of the storage device 11.

The controller 15 performs the operation of the above equation (3) on the input numerical sequence x [k] by using the storage unit 11, the multiplier 12, and the adder 13. For example, assuming that an input numerical value at a certain point in time is x [n], x [n] and a constant b [0] are taken out of the storage unit 11 by the designation of the selection signal output from the controller 15 and the switch 14, and both are taken out. The result is multiplied by the multiplier 12, and the result of the multiplication is stored in the intermediate operation result storage location TMP in the storage unit 11. Further, the value x [n-1] and the constant b [1] of x [n] before quantization are extracted from the storage unit 11 and both are multiplied by the multiplier 12, and the result is compared with the result in the storage unit 11. The value (multiplication result of x [n] and constant b [0]) previously stored in the intermediate calculation result storage location TMP is added to the adder 13.
Then, the result of the addition is stored in the intermediate operation result storage location TMP in the storage device 11. By the above procedure, the input numerical sequence x [n], x [n-1],..., X [nK] and the coefficient sequence b [0], b [1],. , And the output numerical sequence y [n-1], y [n-2],..., Y [nJ] and the coefficient sequence a [1], a [2], .., A [J], the output numerical value y [n] at the time when x [n] is input can be obtained. This output numerical value sequence y [n]
By [j] and b [k], a signal component having a band corresponding to the modulation wave frequency centered on the carrier frequency is extracted from the input numerical sequence x [n].

In the onboard receiver according to the present invention, after the first numerical operation is performed on the input numerical sequence x [n], the output numerical sequence y [n] is further subjected to the first numerical operation. 2
Is performed, and then a third numerical operation is performed. Since these multiply and add operations are repeated, for convenience, the input numerical sequence x [n] and y [n] are respectively converted into a two-dimensional array z [1, n ], Z [2, n]
And the coefficient sequences a [j] and b [k] are represented by a two-dimensional array a [i, j],
Expressed as b [i, k]. Therefore, the above equation (3) is expressed as follows: z [i + 1, n] = Σa [i, j] · z [i + 1, nj] + Σb [i, k] · z [i, nk] 4) k = 0, 1, 2,..., K j = 1, 2,..., J; K and J can be represented as integers. That is, the discrete numerical sequence that the quantization converter 10 quantizes and transforms the signal input through the low-pass filter 9 and stores in the storage unit 11 is represented by z [1, n] and the first numerical operation , And the output numerical sequence of the first numerical operation is represented as z [2, n] and becomes the input numerical sequence of the second numerical operation. Similarly, the output numerical sequence of the second numerical operation is z [3,
n] is the input numerical value sequence of the third numerical operation. Third
Since the number of train control signals I is calculated as will be described later, the output numerical sequence of the numerical operation is calculated as z [4, n], z [5, n],.
, Z [I + 3, n]. FIG. 2 shows an example of the arrangement of the numerical value sequences stored in the storage device 11. The array radix n indicates the newest numerical value in the numerical sequence sampled at a predetermined cycle for each time.

FIG. 3 shows that z [i, n] shown in FIG.
It is an example of the flowchart which shows the flow of a process in the case of performing a numerical operation based on said Formula (4) for every sampling (quantization) period. First, the quantization converter 10 performs an operation on the discrete numerical sequence z [1, n] stored in the storage device 11 to obtain z [2, n].
The first numerical operation processing will be described. First, i =
1. Set k = 0 (S1 and S2). S3-S
In 5, the value of k is added one by one until b becomes
[1, k] is multiplied by z [1, nk], and the multiplication result is added to the numerical value previously stored in the intermediate calculation result storage location TMP and stored. If k> K in S3, then j = 1 is set (S6), and in steps S7 to S9, a [1, j] and z [2 , nj], and the multiplication result is added to the numerical value previously stored in the intermediate operation result storage location TMP and stored. Note that S
Coefficient sequence b [1, k] used in 3-S5 and S7-S9
And a [1, j] are constants determined by frequency selection characteristics for each carrier frequency which are predetermined for each orbital section. Therefore, when a train signal is transmitted at a plurality of carrier frequencies depending on the track section, a coefficient sequence of a transfer function is set corresponding to each frequency, and each numerical operation is performed. If j> J in S7, S
10. Since i = 1, the intermediate calculation result storage location T
The numerical value stored in MP is taken out and the multiplier 1
2, a shift operation or a sign operation is performed, and its absolute value is taken, or a negative value is forcibly set to a zero value (FIG. 3
In the flowchart of (1), only the case of taking an absolute value is shown), and the data is stored in the storage location of z [2, n] in the storage device 11 (S11). The numerical sequence z [2, n] obtained by the processing of S1 to S11 is obtained by expanding the modulated wave component of the carrier frequency band into the baseband of the modulated wave band.

Next, the second numerical operation processing based on the transfer function having the low-pass characteristic for the numerical sequence z [2, n] will be described with reference to the flowchart of FIG.
In step S11, the output numerical value sequence z of the first numerical operation processing
When [2, n] is obtained, i is incremented by 1 to 2 (S12), and S
Return to 2. Then, similarly to the first numerical operation, k is set to 0 (S2), and in S3 to S5, b [2, k] and z [2, nk], and adds the multiplication result to the numerical value previously stored in the intermediate operation result storage location TMP and stores the result. The coefficient sequence b [2, k] used at this time is a constant determined by the low-pass characteristic. If k> K in S3, j = 1 is set next (S6), and in S7 to S9, a [2, j] and z [3 , nj], and the multiplication result is added to the numerical value previously stored in the intermediate operation result storage location TMP and stored. The coefficient sequence a [2, j] used at this time is also a constant determined by the low-pass characteristic. If j> J in S7, the process proceeds to S10 and i
= 2, the numerical value stored in the intermediate operation result storage location TMP is extracted and stored in the storage location of z [3, n] in the storage device 11 (S13). Then, the processing in that cycle ends. The numerical sequence z [3, n] obtained by the processing of S2 to S10 and S13 is obtained by extracting a modulated wave numerical sequence from which a frequency component higher than the modulated wave frequency band has been removed.

Next, a third numerical calculation process based on a transfer function having a frequency selection characteristic for each train control signal for the numerical sequence z [3, n] will be described with reference to the flowchart of FIG. Since the numerical sequence z [3, n] is a modulated wave numerical sequence that is a low frequency, the third numerical operation is performed by sampling (quantization).
It suffices to perform the calculation every time the cycle is multiplied. The calculation based on the following equation (5) is performed on the numerical sequence z [3, n] extracted from the storage unit 11 every time the sampling cycle is multiplied. Note that the multiplication order is T
And z [i + 1, n] = Σa [i, j] ・ z [i + 1, n-jT] + Σb [i, k] ・ z [i, n-kT] (5) k = 0 , 1,2, ..., K j = 1,2, ..., J i = 3,4, ..., I + 2; K,
J and I are integers. In the storage device 11, I types of modulated wave frequencies corresponding to each of the I types of train control signals are preset.
Coefficient sequences a [i, j] and b [i, k] based on transfer functions having frequency selection characteristics are stored for each of the I types of train control signals. FIG. 4 is an example of a flowchart showing an operation performed every time the sampling (quantization) cycle is multiplied. i = 3 is set (U1). If U ≦ I + 2 at U2, k = 0 is set (U3). In U4 to U6, b [i, k] is multiplied by z [i, n-kT] until the value of k is incremented by 1 until K is reached.
The multiplication result is added to the numerical value previously stored in the intermediate calculation result storage location TMP and stored. If k> K in U4, j = 1 is set next (U7), and in U8 to U10, the value of j is incremented by one until J becomes a.
[i, j] is multiplied by z [i + 1, n-jT], and the multiplication result is added to the numerical value previously stored in the intermediate calculation result storage location TMP and stored. If j> J in U8, proceed to U11,
The numerical value stored in the intermediate calculation result storage location TMP is taken out and stored in the storage location z [i + 1, n]. And i
And returns to U2. From the above, z [4, n], z [5,
.., z [I + 3, n] are obtained for each of the I types of modulated wave frequencies.

Next, for each of the I-type numerical sequences obtained by the third numerical operation, the execution value or the maximum value is determined within a predetermined time zone caused by the finite number of numerical arrays. The result obtained by the calculation is compared with a predetermined minimum operation level value. If the minimum operation level value is equal to or greater than the minimum operation level value, the numerical value sequence of the modulated wave frequency is determined to be valid. If a numerical sequence of a plurality of modulation wave frequencies is determined to be valid, a speed indication corresponding to a higher level is selected by an operation level comparison, or a speed indication corresponding to each modulation wave is low. A low-order superiority determination for selecting one is performed. In some sections, the speed indication is constituted by a combination of a plurality of train control signals with a plurality of types of carrier frequencies, and in this case, the indication is determined by a combination of the control signals with the plurality of modulated waves. The controller 15 outputs a train speed signal according to the present determination result via the output device 16 and drives the braking device 17. Further, at the time of inspection and maintenance, various coefficient sequences stored in the storage device 11 can be read out from the input / output device 18 and displayed for confirmation, and the coefficient values can be changed and input to be transmitted to the storage device 11.

As described above, the analog signal received from the ground is quantized into a discrete numerical sequence, and the discrete numerical sequence is subjected to a transfer function having a frequency selection characteristic for each carrier frequency and a transfer function having a low-pass characteristic. , And a numerical operation based on a transfer function having a frequency selection characteristic for each train control signal is performed on a simple circuit composed of the multiplier 12, the adder 13, and the storage unit 11, and signal separation and detection demodulation for each carrier frequency are performed. , And a simple configuration in which the result of signal separation for each modulation control signal is developed for each of the divided areas on the storage device 11, so that the entire apparatus can be significantly reduced in size. The coefficient values used for the numerical operation are stored in the storage unit 11.
Since the input / output device 18 is connected to the controller 15 at the time of maintenance and inspection, the coefficient value in the storage device 11 is displayed on the input / output device 18, and a change can be input.
The frequency characteristics and demodulation method related to signal separation can be easily changed, and the versatility and maintainability of the device are improved.

Embodiment 2 In the first embodiment, in the first numerical operation, the second numerical operation, and the third numerical operation, a method of obtaining a numerical sequence by a transfer function represented by Expression (4) or Expression (5) is used. As described above, even if a numerical operation based on a non-recursive transfer function having a frequency selection characteristic represented by the following equation (6) is performed, the same effect can be obtained, and the amount of calculation can be reduced. This is advantageous in real time. In general, a transfer function having an Nth-order frequency selection characteristic has a form of H (z) = Σc [k] · z ^(−k) k = 0, 1,..., N; It is expressed as c [k] is a constant determined by the frequency selection characteristic, and is stored in a predetermined location in the storage device 11 in advance. If this is expressed by the relational expression between the input numerical sequence and the output numerical sequence, z [i + 1, n] = {c [k] · z [i, nk] (6) k = 0,1 ,. .., N i = 0, 1,..., I; The calculation of the above equation (6) is performed in the storage unit 11, the multiplier 12, and the adder 13 by the designation of the selection signal output from the controller 15 and the switch 14, whereby the first embodiment is performed.
As in the case of the above, it is possible to obtain a numerical sequence whose frequency is selected by the transfer function having the frequency selection characteristic.

Embodiment 3 FIG. Similar effects can be obtained by performing a numerical operation based on a series low-order transfer function having a frequency selection characteristic represented by the following equation (7).
Calculation errors can be reduced. Decomposing a transfer function having an Nth-order frequency selection characteristic into a quadratic product form:
For example, H (z) = Π (Σb [i, k] · z ^(−k) / (1−Σa [i, j] · z ^(−j) )) k = 0,1,2 j = 1, 2 i = 0, 1,..., N / 2; expressed as an integer. a [i, j] and b [i, k] are constants determined by the frequency selection characteristics, and are stored in predetermined locations in the storage device 11 in advance. If this is expressed by a relational expression between the input numerical sequence and the output numerical sequence, z [i + 1, n] = Σa [i, j] · z [i + 1, nj] + Σb [i, k] · z [i , nk] (7) k = 0,1,2 j = 1,2 i = 0,1,..., N / 2; The operation of the above equation (7) is represented by z [1, n], z [2, n],.
Until [N / 2, n] is calculated, the selection signal output from the controller 15 and the switching by the switching unit 14 are repeated in the storage unit 11, the multiplier 12, and the adder 13, thereby obtaining the first embodiment. Or, similarly to 2, a numerical sequence whose frequency is selected by a transfer function having a frequency selection characteristic can be obtained.

Embodiment 4 The same effect can be obtained by performing a numerical operation based on a parallel low-order transfer function having a frequency selection characteristic represented by the following equation (8).
Since parallel processing can be performed, the processing time can be significantly reduced by making the hardware configuration related to the numerical operation parallel. When the transfer function having the Nth-order frequency selection characteristic is expanded into partial fractions, for example, H (z) = Σ ((Σb [i, k] · z ^(−k) ) / (1−Σa [i, j]) Z ^(-j) )) + b0 k = 0,1,2 j = 1,2 i = 0,1,..., N / 2; expressed as an integer. a [i, j] and b [i, k] are constants determined by the frequency selection characteristics, and are stored in predetermined locations in the storage device 11 in advance. If this is represented by the relational expression between the input numerical sequence and the output numerical sequence, z [i + 1, n] = Σ (Σa [i, j] · z [i + 1, nj] + Σb [i, k] · z [i, nk]) (8) k = 0,1,2 j = 1,2 i = 0,1,..., N / 2; The calculation of the above equation (8) is performed by the designation of the selection signal output from the controller 15 and the switch 14 to the storage unit 11,
By repeating in the multiplier 12 and the adder 13,
As in the first to third embodiments, it is possible to obtain a numerical sequence whose frequency is selected by a transfer function having frequency selection characteristics.

[0028]

Since the present invention is configured as described above, it has the following effects.

An analog signal received from the ground is quantized into a sequence of discrete numerical values, and a transfer function having a frequency selection characteristic for each carrier frequency, a transfer function having a low-pass characteristic, and a train control signal Calculation based on a transfer function having a frequency selection characteristic for each multiplier 1
2. The result of signal separation, detection and demodulation, and signal separation for each modulation control signal performed on a simple circuit composed of the adder 13 and the storage unit 11 is classified into the storage unit 11. Due to the simple configuration of developing the device for each area, the entire apparatus can be significantly reduced in size.

Further, when the effective value of the extracted modulated wave numerical sequence is equal to or higher than the minimum operation level predetermined for the train control signal corresponding to the numerical sequence, the modulation is effective in the numerical sequence. Therefore, it is possible to reliably remove the leakage signal from the adjacent block section and the external noise.

When the modulated wave numerical value sequence corresponding to a plurality of control signals is determined to be valid, the signal presentation is determined by comparing the operation levels or determining the lower priority, so that a safe and more accurate determination can be made. .

Further, even when a train control signal is constituted by a combination of a plurality of train control signals using a plurality of types of carrier frequencies, it is easy to perform a numerical operation based on a transfer function having a selection characteristic for each frequency. Can be determined.

Further, since the transfer function used for the numerical operation is stored in the storage means and read out and used at the time of executing the numerical operation, the frequency selection characteristic and the demodulation method can be easily set, and the versatility of the apparatus is improved. .

Further, since various coefficient values of the transfer function stored in the storage means are displayed on the coefficient value changing means and can be easily changed and inputted, the maintainability is improved.

Further, by using a non-recursive transfer function as the transfer function used for numerical calculation, the amount of calculation is reduced, which is advantageous in real time.

Further, when the transfer function used for the numerical calculation is a serial low-order transfer function, the calculation error is reduced, and more accurate signal determination can be performed.

Further, by making the transfer function used for the numerical operation a parallel low-order transfer function, parallel processing becomes possible and the processing speed can be further increased.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a train control signal on-board receiver according to an embodiment of the present invention.

FIG. 2 is a diagram showing an example of an arrangement of numerical value strings stored in a storage unit 11 of FIG.

FIG. 3 is a flowchart showing a flow of first and second numerical calculation processes according to the first embodiment of the present invention.

FIG. 4 is a flowchart showing a flow of a third numerical operation process according to the first embodiment of the present invention.

FIG. 5 is a configuration diagram showing a conventional train signal on-vehicle receiver.

[Explanation of symbols]

8 Power receiving device as receiving means, 9 Low-pass filter as band limiting means, 10 Quantizing converter as converting means, 11 Storage device as storing means, 12 Multiplier as operating means, 13 Operating means as operating means Adder, 15
A controller as validity determination means and presence determination means;
6 output device, 18 input / output device as coefficient value changing means.

Claims (9)

[Claims] 1. A train control signal having a predetermined carrier frequency for each track closing section is received by a receiving means on a vehicle, and a signal indication corresponding to the received signal is determined. In a train control signal on-board receiver that outputs the determination result, of the signals received by the receiving means, band limiting means for limiting high frequency components of a predetermined frequency or higher, and the frequency components are limited by the band limiting means. Converting means for quantizing the analog signal into a discrete numerical sequence, performing a numerical operation on the discrete numerical sequence based on a transfer function having a frequency selection characteristic for each carrier frequency, and modulating the carrier wave frequency with the carrier frequency as a center. First extracted signal component having a band
A first calculating means for calculating a numerical sequence of the first numerical sequence, performing a numerical operation on the first numerical sequence based on a transfer function having a low-pass characteristic, and extracting a signal component having a modulated wave frequency band. A second arithmetic means for calculating a numerical sequence of 2, a numerical operation is performed on the second numerical sequence based on a transfer function having a frequency selection characteristic for each train control signal, and modulation corresponding to the train control signal is performed. Third calculating means for calculating a third numerical sequence obtained by separating signals for each wave frequency, validity determining means for determining whether the third numerical sequence satisfies a predetermined condition, and validity determination A train control signal on-vehicle receiver comprising: a display determination unit that performs a display determination in accordance with the train control signal corresponding to the third series of numerical values. 2. The validity determining means determines that the third sequence is valid if the effective value of the third sequence is equal to or higher than a minimum operation level predetermined in a train control signal corresponding to the third sequence. The train control signal on-vehicle receiver according to claim 1, wherein the on-vehicle control signal is to be determined. 3. When the validity judging means judges that a plurality of third numerical sequences are valid, the presenting judging device performs an operation level comparison or a superiority judgment between train control signals corresponding to these numerical sequences. The train control signal on-vehicle receiver according to claim 1 or 2, wherein the signal indication is determined. 4. When a plurality of carrier frequencies are predetermined for each track section and a plurality of train control signals are received by the plurality of carrier frequencies, first to third numerical operations are performed. The extracted third numerical sequence is determined to be valid, and the presentation determination unit determines that the signal presentation is determined by a combination of a plurality of train control signals corresponding to the plurality of third numerical sequences determined to be valid. Claim 1.
Or the train control signal on-vehicle receiver according to 2. 5. The apparatus according to claim 1, further comprising storage means for storing transfer functions used for the first calculation means, the second calculation means, and the third calculation means. A train control signal on-board receiver as described. 6. The train control signal on-vehicle receiver according to claim 5, further comprising coefficient value changing means for changing each coefficient value of the transfer function stored in the storage means. 7. The train control signal according to claim 1, wherein a transfer function used in the first operation, the second operation, and the third operation is a non-recursive transfer function. On-board receiver. 8. The train control according to claim 1, wherein a transfer function used in the first calculation, the second calculation, and the third calculation is a serial low-order transfer function. Signal car receiver. 9. The train control according to claim 1, wherein transfer functions used in the first calculation, the second calculation, and the third calculation are parallel low-order transfer functions. Signal car receiver.