JPS606580B2 - Data and point information transmission device to mobile objects - Google Patents

Description

[Detailed Description of the Invention] When an automation system controls the running of a mobile object such as a vehicle or a crane that moves along a certain travel route, control is performed between the mobile object and a control device fixed on the ground (hereinafter referred to as a ground station). In addition to being able to send and receive monitoring data, it is also necessary to detect the location of a mobile object in order to automate the travel of the mobile object.

In this case, the present invention particularly provides a mobile communication device between the mobile body and the ground station, which allows data to be transmitted from the ground station to the mobile body at any time, and at the same time the mobile body receives the data and simultaneously detects a fixed point on the travel route. Regarding. As a method for a mobile object to detect a predetermined point along a travel path, a crossing parallel two-wire guide wire is laid out along the travel path, a signal current is passed through the guide wire, and this current is detected by the mobile object. So-called guided radio type phase discrimination position detection devices have been proposed that detect phase changes at intersections by receiving signals in a guided manner, but these are only for fixed point detection and are not used for data transmission between a mobile object and a ground station. In order to do this, it is necessary to separately provide data transmission equipment, which poses a problem in that the equipment becomes expensive. The present invention eliminates this drawback and makes it possible to not only detect each of a plurality of fixed points along the traveling route on the moving object side while the moving object is running, but also to be efficient in that it enables mutual data communication with the ground station at all times. The system provides a communication method that is easy to use, and will be explained in detail below. First, we will explain how to detect point information (speed, position, etc. of a moving object) using guide lines.

FIG. 1 is a diagram illustrating the configuration principle of a point information detection device. This figure shows that the crossing parallel two-wire guide wire 6 laid along the running route is one
In the case of only 1, 1 has 2 frequencies (f and f2)
A transmitter, 4 a coupler, and 5 a terminating resistor. 2 on the ground side
From the frequency transmitter 1, both the f,wave and the f2 wave, which has a frequency different from the f,wave and have a relationship of f,=(m-1)/m (m is an integer of 2 or more), are unmodulated. The signal is outputted at the output terminal and passed through the coupler 4 to the guide wire. 2 and 3 are equipment installed on the moving body; 3
2 is an antenna that moves while being connected to the guide line 6, and 2 is a fixed point detector that detects a fixed point on the road, that is, a point where the guide line 6 intersects.

The phase of the signal induced in the antenna 3 is the same as that of the mobile object in Figure 1.
Alternatively, the phase of the voltage or current differs by 180° between the case in section c and the case in section b or d. Therefore, when the antenna 3 passes over intersections A, B, C, etc., the signal phase changes by 180 degrees, so the fixed point position can be detected by detecting the phase change. In other words, both the f and f2 waves coupled and output to the antenna 3 are separated and extracted by their respective radio wave generators, and if the f and wave are multiplied by a doubler, the frequency will be doubled, = f2. , 1 due to the intersection of the guide lines
800 Even if the phase is reversed, the double wave as described above becomes a continuous phase wave without phase reversal (this can be easily understood from the waveform when double multiplication is obtained by full-wave rectification, for example). The fixed point position is detected by distinguishing the phase of the f2 wave, which is the output of the other band wave generator, as a phase signal wave. Note that the intervals between the intersections are arbitrary, but if they are set at equal intervals, it is convenient for detecting the speed and position of a moving object. Also, the guide wire 6
is not limited to one, but it is also possible to provide position information of a moving object by having a plurality of them in parallel and changing their intersection locations, but this is not related to the present invention and will not be described here. Note that two frequencies f,, which have a relationship of f, = (m-1) et al/m,
Regarding the method of detecting the position of a moving object using f2, the present applicant has previously proposed Japanese Patent Application No. 1983-79952
No. 4-14766), Japanese Patent Application No. 1983-83019 (
Japanese Unexamined Patent Publication No. 18569/1982), Patent Application No. 113/1983
No. 195 (Japanese Unexamined Patent Publication No. 54-47676) provides a detailed explanation. Next, FIG. 2 is a diagram showing an example of the basic configuration of a communication device embodying the present invention.

In this figure, reference numeral 7 denotes a guide line extending along the running route of the data transmission section Dd, Rd denotes its terminal resistance, and 8 denotes a ground station transmitter, which includes a data transmitter and a point information signal transmitter. . 9, 1 river combiner, 11 is point information detection section D
Ra is a guide line that extends over a and intersects at every fixed point.
is its terminating resistance.

12 and 13 are equipment to be mounted on the moving body, 12 is the guide line 7
and an antenna (antenna coil) coupled with 11, 1
3 is a receiver consisting of a data receiver and a point information detector.

Now, the ground station transmitter 8 includes a two-frequency oscillator with two frequencies f and f2 similar to 1 above, and a modulator that performs phase-shift keying (PSK) on the f and wave using the amplifier and data (binary code). ``The PSKed f.
If the relationship is an integer greater than or equal to 1, the waves are sent out to the intersecting parallel two-wire guide wire 11 without modulation. For convenience, the following explanation will be based on the case where m = 2, but if m is 2
Similar operation can be obtained in other cases as well. When m=2, L=f2/2. FIG. 3 is a block diagram of an example circuit configuration of the mobile receiver 13.

The top stage of FIG. 3 is a PSK signal demodulation section or a data reception section,
The second and subsequent stages can be called a point information detection section. 14
, 18 are bandpass filters (BPFs) that extract f, waves, and f2 waves, respectively; 15, 19 are amplifiers and amplitude limiters; 16 are PSK signal demodulators; 17 is a frequency doubler (m=2 ), 20 is a phase discriminator, and 21 is a point information output device.

An example of the operation waveforms of each part in FIG. 3 is shown in FIG. 4, and the operation in FIG. 3 will be explained next using FIG. 4. The top row of FIG. 4 is a data signal Z. If this Z signal is input as the modulation input Din of the data transmitter of the ground station transmitter 8 in FIG. That is,
As is well known, this system includes 2-phase, 4-phase, 8-phase...
...・There is a 2m phase method), but currently 2m phase modulation is used.
As phase modulation, if the signal is "1" for each bit of input data, the phase is shifted; if it is "0", there is no shift, and the fz in Fig. 4 is applied.
A waveform current is passed through the guide wire 7 as a wave. Note that 1 to 8 shown above the Z waveform in FIG. 4 represent bit numbers, SP represents a stop, ST represents a start, and 0 below the Z waveform represents a phase. On the other hand, since the waves flow through the guide wire 11 while maintaining the relationship, the antenna 12 of the mobile body picks up the f, wave and f2 wave from both the guide wires 7 and 11 and inputs them to the receiver 13. L, . is the guide wire 11
The intersection is shown for convenience, and the operation of the receiver 13 changes as follows on the left and right of the intersection. However, it is assumed that the moving object moves at a constant speed. First, the f2 wave from the intersecting guide wire 11 is induced into the antenna 12 with its phase reversed at the intersection of L, as shown in the waveform d in FIG. From these waves, only the f2 wave component is extracted by the BPF 18 in FIG. 3, and the signal, which is amplified and amplitude-limited at 19 and has a constant level, becomes one input of the phase discriminator PD20. Next, the f wave from the other guiding wire 7 is extracted by the BPF 14 in Fig. 3, and the f component is amplified and amplitude limited at 15, and then the frequency is doubled at 17, resulting in an e waveform of = f2. can get. When the wave f, is multiplied by 2, the phase modulated wave becomes a continuous phase wave e with zero shift amount, so this is used as a reference phase signal and the phase discriminator P is used.
into the other input of D20. In addition, in the case of f, = f2 no 2, the f, wave can be multiplied by 2 using the frequency transmitter 17 as described above, but in the general case where f, = (m-1) etc./m, By extracting the frequency of the difference between the f, wave and the f2 wave and multiplying it by m (frequency), a continuous phase wave with a shift amount of zero can be obtained, and this is used as a reference phase signal. Now, the phase discriminator PD20 discriminates whether the above two inputs (d waveform and e waveform) are in phase or out of phase and outputs it, but this PD20 includes a reduction waveform generator and a square wave converter, and the waveform shown in FIG. As shown in , for example, if the phase is the same, the level is H, and if the phase is out of phase, the level is L.
Each output g of a level is generated. Note that the BPF 18, amplifier 19, etc. generally have a unique phase shift amount, but since these cannot be predicted, it is necessary to insert a phase shift correction circuit into the PD 20 input to make the ideal phase difference. It is. Further, the point information output device D21 to which the g input is given generates a pulse h from the conversion point of the g waveform and outputs this as a fixed point detection pulse. If the guide line 11 is crossed at a fixed point on the travel route in this way, the fixed point can be detected on the moving object side when the moving object passes. Therefore, for example, if the distance between the intersections of the guide line 11 that intersects the point information detection section Da is D, then when the detection of these two fixed intersections is performed at a time interval of t, the travel distance between these two points is Over time, the average speed of the moving object within a distance of D is D,/t. It is also possible to determine the position of the moving object on the road by counting the number of fixed points (the number of pulses h) for each intersection using the first intersection in section Da as the starting point. On the other hand, for data transmission, for example, the DPSK f wave is transmitted from the guide line 7 through the antenna 12 to B in FIG.
The signal that enters the PF 14, is amplified and then limited to a constant amplitude is sent to the phase shift signal detector 16 (DTC).

DTC16 uses secondary DPSK (differential phase shift keying)
This is because the i waveform shown in Figure 4 is output from the internal phase discriminator by means of wave demodulation (the phase difference between the preceding bit signal delayed by one bit time and the subsequent bit is detected for each bit by a phase discriminator). , converted into a square wave by a low-pass waveform generator and a Schmitt circuit (none of which are shown) following the DTC 16, or converted into a square wave by an integral-to-stand waveform generator, and the data on the transmitting side 8, that is, the Z waveform in FIG. The same signal can be restored. As explained in detail above, in the device of the present invention, the data transmission signal wave f is transmitted from the ground station to the non-crossing concession line 7, and the unmodulated f2 wave is transmitted as a point information signal wave to the guide line 11 which is crossed at each fixed point. By sending the data to the respective locations, the mobile device can receive data and detect a fixed point at the same time.

Furthermore, if a data signal transmitter is installed in the mobile body and the data transmission signal wave f, (or wave f3, which is different from f and f2) is transmitted to the ground station via the guide wire 7, the receiver at the ground station is transmitted. It is clear that the mobile unit can be configured to receive data from a mobile unit. In the present invention, since a phase discrimination method using intersecting guide lines is used as a method of detecting a fixed point, the use of an amplitude limiter is permitted. Therefore, even if the distance between the mobile antenna 12 and the guide wires 7 and 11 changes as the mobile moves, and the coupling loss between them changes significantly, the crossing position can be detected accurately and with high accuracy. This is a remarkable feature.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the basic configuration of a point information detection device, FIG. 2 is a basic configuration diagram of a communication device that is an embodiment of the present invention, FIG. 3 is an example circuit diagram of a mobile receiver in FIG. 2, and FIG. 4 is a diagram illustrating an example of waveforms at various parts in FIG. 3. FIG. 1...2-frequency transmitter, 2...Fixed point detector, 3
, 12... Mobile antenna, 4, 9, 10...
...Coupler, 5, Ra, Rd...Terminal resistor, 6,7,11...Parallel two-wire induction wire, 8...
...Ground station transmitter, 13...Mobile receiver, 14
, 18...Obijo wave generator, 15, 19...Amplifier and amplitude limiter, 16...OreK signal (data) demodulator, 17... Frequency multiplier, 20...
... Phase discriminator, 21 ... Point information output device. Figure I Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1. A first guide line consisting of two non-crossing parallel lines laid out over the required section of the moving vehicle travel path, and two parallel lines that intersect at predetermined points within the required section on the same plane as this guide line. A data transmission signal current of a first frequency f_1 subjected to two-phase (π-phase) phase shift modulation by a data signal is transmitted from one end of the first guiding wire and the second guiding wire consisting of a wire. Consisting of a transmitter that supplies the point information signal current of the first frequency f_1 and the unmodulated second frequency f_2, which has a relationship of 2f_1=f_2, from one end of the second guide wire on the same side as the first guide wire. ground station equipment, an antenna that is coupled to both the first and second guiding wires and outputs signal currents of both the first and second frequencies; A bandpass filter that extracts each frequency component, an amplification/amplitude limiter that amplifies each filter output and limits it to a constant amplitude, and a part of the output of the first frequency f_1 among these outputs is input. a phase shift signal demodulator that demodulates and outputs a two-phase phase shift keying data signal; and a frequency that doubles the other output of the first frequency f_1 and outputs a reference phase signal of frequency 2f_1 (= f_2). a second frequency f_2 of the multiplier and the amplitude limiter;
and a phase discriminator that discriminates the phase difference between the output of the above and the reference phase signal output, and a moving object equipment comprising a point information output device that outputs a fixed point detection pulse every time the moving object passes a fixed point based on the discrimination output. A device for transmitting data and point information to a mobile object.