JPS6057776B2 - Mobile object position detection and information signal transmission equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mobile body moving on a fixed traveling path and a ground fixed station (
This technology relates to a device for transmitting information signals between ground stations (hereinafter referred to as ground stations) using a guided radio method and for detecting the location of a moving object on a segmented route. One of its features is that the signal frequency and transmission path can be shared for information transmission and position detection.

Conventionally, a feedback oscillation circuit is formed by utilizing mutual proximity coupling of devices installed on the ground and on a moving body at a fixed point on a travel route, and the oscillation frequency is set to a value predetermined for the type of information. Fixed point type, in which the moving body or ground station detects the frequency oscillated when the moving body and ground equipment approach each other and the degree of electromagnetic inductive coupling increases, and information is transmitted, and the parallel two-wire type, which is installed along the running route. Information signals are transmitted between a ground station with an information signal transmitter and receiver connected to one end of the guide wire, and a mobile station equipped with an antenna installed on a mobile body and inductively coupled to the guide wire, and a receiver for transmitting information signals. A continuous type is known that transmits and receives information, but a fixed point type transmits information and detects the position at a fixed point. However, although the continuous type transmits information continuously, it is impossible to detect the position of a moving object on the road and a position detection device must be provided separately.

A parallel two-wire system with guiding wires crossing at regular intervals is used to transmit information signals. Although there are methods that allow both position detection, the problem remains that information signals cannot be transmitted at intersections and that the error rate is extremely low. The present invention eliminates the above-mentioned drawbacks, and also makes it possible to achieve this at a lower cost compared to conventional equipment, which requires a minimum of one piece of equipment with multiple functions in recent applications such as automatic operation control and automatic driving of vehicles. In particular, even vehicles with rubber tire wheels can continuously transmit information signals while the vehicle is running, and the position of a moving object on the road can be detected using the same frequency signal. This feature is explained in detail below with reference to the drawings. FIG. 1 shows an example of the configuration of the apparatus of the present invention, in which an information signal Di is transmitted from a mobile object to a ground station and the position of the mobile object is detected by the ground station.

In this figure, 1 and 3 are parallel two-wire guide lines extending along the traveling path of the moving object, and the traveling path is divided into sections A, B,
The two lines intersect at the dividing point C. 2 is a guide wire extended between the two wires in the same plane as the two wires of the crossed guide wire, R is a terminal impedance or resistor connected to one end of the guide wires 1 and 2, 2 and 3, respectively; 4 is a first transformer in which a primary (side) coil is connected between the other ends of the induction wires 1 and 3, and between the neutral point tap of the primary coil and the other end of the induction wire 2. The primary coil of the second transformer 5 is connected.

Next, guide wires 1 and 2 are connected to the moving objects for these ground facilities.
, 3 are provided. Loop antenna coils 6 and 7 are provided.

St6 is a crossed loop coil, and the guide wires 1 and 2 are connected to each other.
, 3 (transformer 5
The so-called induction wire 1 generates an induced output with respect to (by the secondary input of the , 3 and 2, and 7 is a non-crossing loop coil, which has a current flowing only in the induction wires 1 and 3 with a phase difference as shown by the broken line arrow (due to the secondary side input of the transformer 4). This is a so-called loop coil connected to the induction wires 1 and 3, which generates an induced output or induces currents having a phase difference as indicated by the broken line arrows only in the induction wires 1 and 3 by its internal current. Further, in the example of FIG. 1, 8 to 10 are transmitting equipment installed on a mobile body, and information DI on the mobile body side is encoded in an encoder 10 and then sent to a modulator 9. This modulation method is known as on-off keying,
Either FSK or PSK may be used, but here DPSK is used.
Assuming that (differential phase shift) modulation is performed, DP
The modulated signal subjected to SK modulation is generally input to a transmitter 8 of LF or
1 transmission frequency and power amplification are performed, and the output is supplied to loop coils 6 and 7. Next 11
~17 is the reception detection equipment on the ground station side, and the induced signal from the loop coil 6 is connected to the flow transformer 5 with the phase relationship shown by the solid line arrow.
An output is generated only on the secondary side of the transformer 4, and the induced signal from the loop coil 7 generates an output only on the secondary side of the transformer 4, which flows in the phase relationship shown by the broken line arrow. Note that the mutual coupling between transformers 4 and 5 is almost zero, and the induction line consisting of 1 and 3 and the induction line consisting of 2 and 1,
It is assumed that the guide lines consisting of 3 are well balanced and the coupling between them is extremely small. Specifically, transformer 4-2
The secondary side output of the transformer 5 is zero with respect to the input from the next side, and conversely, the secondary side output of the transformer 4 is zero with respect to the secondary side input of the transformer 5.
Adjust the terminal resistance R of the induction wire and the transformer, especially the balancing resistor (not shown) connected to the primary coil 4, so that the next output is zero.In an example of an actual induction wire, LF If the wire length is -, the coupling loss between both transformers is approximately 60 dB.
A value sufficient for practical use has been obtained. The inductive input from the loop coil 6 is input from the transformer 5 to the VLF receiver 11 and the signal amplification and amplitude limiter (A top) 14, and the inductive input from the loop coil 7 is input from the transformer 4 to the signal amplification and amplitude limiter. Input into the device (A top) 15. First, receiver 11
Then, a signal wave of a specified frequency is selected and extracted, and if necessary for processing, it is also converted to an optimum frequency and inputted to the demodulator (DEM) 12 at the next stage. The demodulator 12 corresponds to the modulation method of the transmitter modulator 9, but in this case, it demodulates DPSK based on the above assumption and sends the demodulated code to the decoder (DE).
C) When sent to 13, the decoder 13 extracts information D from the input code.
. Decode and output. On the other hand, the signal wave from the transformer 5 inputted to the upper A 14 is amplified including selective extraction of the signal wave of a specified frequency, and the amplitude is limited to a constant amplitude, and its output is sent to the next stage phase discriminator (PD ) 16 inputs.

The other input of PDl6 is the input from the transformer 4, which is subjected to selective extraction, amplification, and constant amplitude limitation of the signal wave at A upper 15, which has the same function as A upper 14. Phase discrimination is performed (the phase difference between the two inputs will be explained next) and the discrimination output is sent to the next stage square wave converter (ST).
17 will be sent. STl7 is a square wave conversion circuit including a low-frequency P-wave filter (LPF), and outputs a signal Dp for position detection. Next, the phases of the signal waves output from the transformers 4 and 5 will be explained.

The two parallel lines formed by the guide wires 1 and 3 are crossed at the dividing points of appropriately determined sections of the running route as shown in FIG. Since the loop coil 6 is of a crossed type, the output signal of No. 5 does not cause discontinuity in the phase of the output signal even when the moving body moves and the wires are combined at the intersection of the guide wires. It has a constant continuous phase throughout the entire interval. In addition, the output signal of the transformer 4 obtained by inductively coupling to the loop coil 7 is a non-crossing type output signal of the transformer 4, which is a combined output with the crossed parallel two-wire induction wire (according to 1 and 3). Each time the body travels and passes an intersection, that is, each time the section changes, 180 (π
radians) phase changes. Next, FIG. 2 is a time chart of waveforms of various parts in FIG. 1, and the operation of FIG. 1 will be explained in more detail with reference to this diagram.

In this figure, the information transmission speed and the traveling speed of the moving object are assumed to be constant. The a waveform in the figure is the DP generated by the modulator 9 in Figure 1.
Indicates the phase change of the SK modulated wave, and if the sign from ENClO is “1”, the phase is shifted by π phase (180 signs) with respect to the preceding phase,
If the sign is ゜゜0゛, the phase does not change and becomes a continuous phase. Further, b indicates the position of the intersection of guide lines 1 and 3 in relation to the modulated wave of a. Now, when the waveform a is input to the loop coils 6 and 7, the signal waveform output to the transformer 5 in relation to the intersection point of b and the waveform output to the C1 transformer 4 are respectively expressed as d. For the reason described above, the c waveform is a continuous phase wave that is unrelated to the intersection of b, and the d waveform changes in π phase with the intersection as a boundary. Also, the broken line indicates the amplitude envelope, and the d waveform dips at the intersection.Now, the c waveform is input to the receiver 11 and the A top 14 as described above, demodulated by DEM12, and further decoded by DECl3. information output D.

becomes the waveform e in FIG. 2, which is the same information as the waveform a, and correct information transmission is performed. On the other hand, the d waveform is input to the upper A 15, and its output is input to the next stage phase discriminator PD16 as the waveforms C and d together with the output of the above A 14, but the phase difference is different before the intersection of b, that is, on the left side. In phase, and out of phase on the right side. Therefore, the output of PDlJ6 is, for example, a positive level if the phase is in-phase, and a negative level if it is out of phase, but in the next stage square wave converter 17, the positive level is changed to H (high) level, and the zero and negative levels are changed to L (low) level. The position detection output Dp changes as shown in the waveform f in FIG. 2. Note that there are differences in the amount of phase change in the path from loop coil 6 to transformer 5 and the path from loop coil 7 to transformer 4, and the amount of internal phase change in A upper 14 and A upper 15, so the input of PDl6 Actually, it is necessary to provide a phase correction circuit on the side and adjust the two inputs in advance so that they have an ideal phase relationship. In this way, the output signal D
Since p is inverted and output as either a binary value of 1 or 0 for each section, in the general case where the number of sections is 2 or more, for example, the number of binary inversions can be counted and displayed to know the section in which the moving object exists. I can do it. Since these techniques are well known, further explanation will be omitted in this explanation. In the above explanation, the modulation of the transmitted signal was DPSK, but FSK (frequency shift) modulation or 2
It can be easily inferred that the same function can be obtained by either keying-on or off-keying modulation.

In addition, in the example shown in Figure 1, the information signal is sent from the mobile object side, and the ground station receives the information signal and detects the position (correctly, the area of existence) of the mobile object, but in the opposite direction, the ground station It is also possible to transmit an information signal from the ground station, receive the information signal on the moving body side, and self-detect the position of the existing section on the road. to supply the output of the transmitter 8 to the second and next sides of the transformers 4 and 5, and to provide the information receiving equipment consisting of 11 to 17 in the mobile station and to supply the output of the loop coil 6 to the receiver 11 and the upper A 14. All that is required is to input the output of the loop coil 7 to the upper A 15. It is clear that if both the mobile body and the ground station are equipped with transmitting equipment and receiving equipment and are used selectively, it is possible to transmit information in either direction and detect the position.
Since the transformer and loop coil are shared, it is highly economical.
Furthermore, although the coupling coils 6 and 7 on the moving object side are loop coils in the above example, they are not limited to loop coils. An antenna using one to several antennas can also be used. As explained in detail above, in the present invention, it is possible to continuously transmit information signals using one information signal wave without causing transmission failure or information error rate/deterioration, and at the same time, the information signal wave Since it is possible to detect the section position of a moving object, it is useful for transmitting commands and monitoring information between the vehicle and ground station controller in the operation control of vehicles on a fixed route, or for detecting the vehicle section position and speed in automatic vehicle control. It has a wide range of uses, such as being easy to use for fixed position stop control and position detection such as stop position.

Furthermore, the guide wire included in this device may have a simple configuration, and the transmitting and receiving equipment can use low power and simple circuits or circuit elements, making it an inexpensive and highly reliable device. . BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing an example of the configuration of the apparatus of the present invention, and FIG. 2 is a diagram showing an example of waveforms of each part of FIG.

1, 2, 3... Induction wire, 4, 5... Transformer, 6, 7... Loop coil, 8...
・Transmitter, 9...Modulator, 10...Encoder, Dpi...Information input, DO...Information output, D
p...Position signal output, 11...Receiver, 1
2...Demodulator, 13...Decoder, 14
, 15... Signal amplification and amplitude limiter (A top), 1
6... Phase difference discriminator (PD), 17...
Square wave generator (ST).

Claims (1)

[Scope of Claims] 1. A device for transmitting information from a mobile object moving on a fixed travel route to a ground station and for detecting the position of the mobile object on the travel route at the ground station, and for transmitting information to the mobile object on the travel route. 2 by encoding the information input Di and modulating the transmission carrier wave with its output.
information signal transmission equipment 10, 9, 8 that outputs to each of the three loop coils, and a cross-shaped loop coil 6 that inductively couples the information signal wave to the parallel three-wire guide wire of the ground station and sends it out.
A loop coil facility consisting of a non-intersecting loop coil 7 is mounted on the ground station, and the outer two lines 1 and 1 of the three lines are installed along the mobile vehicle travel route and at the section division points where the travel route has been divided in advance. Parallel 3-wire guide wires 1, 2 with intersection between 3,
3, and a first terminal terminally connected between two outer wires at one end thereof.
The cross-shaped loop coil 6 of the movable body coupled to the guide wire is composed of a transformer 4 and a second transformer 5 which is terminated between the midpoint of the first transformer and the center line 2 of the guide wire. A guide line equipment for outputting the information signal input from the second transformer and the information signal input of the non-crossing loop coil 7 from the first transformer, and a guide wire equipment for outputting the information signal input from the second transformer 5 from the moving body. The information receiving equipment 11 to 13 receives and demodulates and decodes the information signal wave to obtain the information output D_o, and the outputs of the first transformer 4 and the second transformer 5 are separately amplified and amplitude limited. Position detection signal output circuits 14 to 17 that discriminate the phase difference between the two output signals, convert the output into a square wave, and output a position detection signal Dp indicating the position of the moving body due to the intersection made on the guide wire. What is claimed is: 1. A mobile body position detection and information signal transmission device, characterized in that a mobile body position detection and information signal transmission device is installed with a mobile body to receive information signals and detect the position of the mobile body. 2 A device that transmits information from a ground station to a mobile object moving on a fixed travel path and detects its own position on the travel path on the mobile object side, and the information input D to be transmitted to the ground station.
information signal transmission equipment 10, 9, 8 that generates an information signal transmission wave which encodes i and modulates a transmission carrier wave with its output;
Parallel three-wire guide lines 1, 2, and 3 that intersect the outer two lines 1 and 3 of the three lines along the travel path of the moving object and in accordance with the section division points where the travel path has been divided in advance. It consists of a first transformer 4 whose termination is connected between two outer wires at one end, and a second transformer 5 whose termination is connected between the midpoint of the first transformer and the center wire 2 of the guide wire. Said first
and a guide line equipment input to the second transformer is installed, and the information signal wave from the second transformer 5 is inductively coupled to the three wires 1, 2, and 3 of the parallel three-wire guide wire to the moving body. A cross-shaped loop coil 6 which combines and outputs
a loop coil facility consisting of a pair of non-crossing type loop coils 7 which inductively couples the information signal wave from the first transformer 4 and outputting the information signal wave from the output of the crossing type loop coil 6; After receiving demodulation and decoding, information signal D_
o, and the outputs of the pair of loop coils 6 and 7 are separately amplified and amplitude limited, the phase difference between the two output signals is discriminated, and the output is converted into a square wave. Position detection signal output circuits 14 to 17 for converting the signal and outputting a position detection signal Dp indicating the position of the moving body based on the intersection made on the guide line are installed to receive information from the ground station and to receive the self-position. A mobile object position detection and information signal transmission device characterized by performing detection.