JPH0543069B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is applicable to mobile objects (various transportation systems including linear motor cars) that use guided radio to move along a certain running route (track, etc.). The present invention relates to a method for periodically and continuously detecting the position of an industrial transport engine on a moving body. [Conventional technology] Accurately grasping the position of moving objects such as railway vehicles, various industrial transport systems, new transportation systems, etc. that move along a certain travel route at all times is the most fundamental aspect of automated operation of these moving objects. This is a specific request. A method for detecting the distance from the starting point of a moving object's travel path is to subdivide the driving path into unit sections of equal length, convert each section into an address, and detect which unit section the moving object is located within. It is common to use a combination of (rough absolute banchi method) and a method (relative position detection method) that continuously detects the distance to the moving object starting from one end of each unit section. Control methods for the movement of moving objects are broadly divided into centralized control methods and distributed control methods.Moving object position detection is divided into ground detection methods in which the position of each moving object is detected at a ground base station, and However, with the recent rapid development and spread of microcomputers, distributed control methods, in which each moving object autonomously drives itself according to its own driving program, are gradually becoming more widespread. Along with this, on-vehicle methods are increasingly being used to detect the position of moving objects. FIG. 5 shows an example of a method currently proposed for detecting the position of a moving object on a moving object within a unit section (lowest address) arranged at regular intervals. Reference numerals 1a and 1b each represent a conductor, and these conductors are bent into a waveform shape at a constant period P, and the guided radio line 4 is formed by arranging them at a distance of P/3 in the longitudinal direction. Reference numerals 2a and 2b are antennas (frame-shaped loop coils) mounted on the moving body, and are arranged shifted by P/4 in the longitudinal direction of the guided radio line 4. A signal processing circuit 3 processes the output voltages of the antennas 2a and 2b and derives position information of the moving body. A transmitter 5 is placed at the starting end of the guided radio line 4 and supplies high frequency current to the conductors 1a and 1b. 6 is the running path of the moving object, which has a certain length l
By subdividing the unit intervals A ₁ , A ₂ , A ₃
It is divided into... Unit sections A 1 , _{A 2 of} period P of conductors 1a and 1b,
The relationship between A ₃ ... and the length l is set to be P=2l. In such a configuration, antennas 2a and 2b
Assuming that the output voltages of are Va and Vb, respectively, the following relationship holds between these voltages and the moving body position z. Va=k cos2π/Pz・e ^- 〓 ^zj 〓 ^z+j 〓 ^t Vb=k cos2π/P(z+1/4P)・e ^- 〓 ^zj 〓 ^z+j 〓
^t = k cos(2π/Pz+π/2)・e ^- 〓 ^zj 〓 ^z+j 〓 ^t …
...(1) k is a constant, α and β are the attenuation constant and the above constant of the guided radio line, respectively. Transforming the above, Va=1/2k(e ^j2 〓 ^z/P +e ^-j2 〓 ^z/P )・e ^- 〓 ^zj 〓 ^z+j
〓 ^t Vb=1/2k(e ^j2 〓 ^z/P+j 〓 ^/2 +e ^-j2 〓 ^z/P+j 〓 ^/2 )・e
^- 〓 ^zj 〓 ^z+j 〓 ^t ...(1-1), where the positive sequence voltage Vp and the negative sequence voltage Vn
is defined by the following equation. Vp=Va+e ^-j 〓 ^/2・Vb Vn=Va+e ^j 〓 ^/2・Vb ...(2) Substituting equation (1-1) into equation (2), Vp=1/2k(e ^j2 〓 ^{z/ P} +e ^-j2 〓 ^z/P +e ^j2 〓 ^z/P+j 〓 ^/2-
j 〓 ^/2 +e ^-j2 〓 ^z/P+j 〓 ^/2-j 〓 ^/2 )・e ^- 〓 ^zj 〓 ^z+j 〓 ^t 1/2k(e ^j2 〓 ^z/P +e ^-j2 〓 ^z/P +e ^j2 〓 ^z/P +e ^-j2 〓 ^z
/Pj 〓)・e ^- 〓 ^zj 〓 ^z+j 〓 ^t =ke ^j2 〓 ^z/P- 〓 ^zj 〓 ^z+j 〓 ^{t
Vn=1/2k(e j2 〓 z/P +e -j2 〓 z/P +e j2 〓 z/P+j 〓 /2+
j 〓 /2 +e -j2 〓 z/Pj 〓 /2+j 〓 /2 )・e - 〓 zj 〓 z+j 〓 t 1/2k(e j2 〓 z/P +e -j2 〓 z/P +e j2 〓 z/P+j 〓＋e -j
2 〓 z/P )・e - 〓 zj 〓 z+j 〓 t =ke -j2 〓 z/P- 〓 zj 〓 z+j 〓
t ...(3), and the phase angles of both voltages Vp and Vn are respectively ∠Vp and
Assuming ∠Vn, the phase difference φ between both voltages can be expressed as in the following equation. φ=∠Vp−∠Vn=4πz/P...(4) In other words, as shown in Fig. 6, the phase difference φ shows a linear increase of 2π every time z increases by P/2, and the position The moving body position z is determined by measuring the value of the phase difference φ.
can be measured continuously at periodic points within the range of P/2. In this case, by making the period P/2 coincide with the unit interval length l, and by making the point where the phase difference φ transitions from 2π to 0 coincide with the boundary point of each unit interval A ₁ , A ₂ , A ₃ . , the position (relative position) within the unit interval can be known. Although the interior of the signal processing circuit 5 is not specifically shown, the above-mentioned calculations can be easily realized by an analog calculation circuit composed of a phase shifter, an adder, a phase comparator, and the like. In addition, the above method assumes that the output of the antenna is purely sinusoidal with respect to the coordinate z of the moving body, but this requires appropriate selection of the dimensions of the antenna and the separation distance between the antenna and the guided radio line. By doing so, it is possible to obtain a sinusoidal coupling distribution waveform of substantially pure water. Furthermore, by making the guided radio line 4 have a structure in which the conductors 1a and 1b are shifted by P/3, the 3rd, 9th, 15th... spatial harmonics included in the coupled distribution waveform are canceled out, and the resulting position detection error is reduced. It is possible to make it disappear. [Problems to be solved by the invention] However, according to the above-mentioned position detection method,
The cycle of relative position detection of a moving body is P/2, and therefore the laying cycle of the conductor of the guided radio line must be twice the unit section length l (P=2l).
It is extremely difficult to realize a structure of a guided radio line with such a long period, and there is a risk that the accuracy of laying the conductor will be lowered, and the accuracy of detecting the position of a moving object will be lowered. In addition, the prerequisite for the above vehicle body position detection to be successful is that the coupling distribution waveform between the guided radio line and the antenna must be a pure sine wave. It is necessary to set the antenna length) in the range of P/7 to P/3, and the antenna dimensions increase in proportion to the increase in the conductor period, which causes an economic disadvantage.
Various disadvantages also occur in terms of mounting the antenna on a moving object. The present invention has been made based on the above, and an object of the present invention is to make the detection cycle of a moving object position equal to the guided radio line conductor period P, thereby facilitating the production of a guided radio line and downsizing the antenna. It is. [Means for Solving the Problems] The gist of the present invention is to install a guided radio line in which a reciprocating conductor bent into a waveform shape with a constant period P is arranged with a shift of P/3 in the longitudinal direction of the line. The guided wireless lines are laid along the running path, and by passing a high frequency current through them, a high frequency magnetic field distributed in a sinusoidal manner in the longitudinal direction of the guided wireless lines is formed, and the guided wireless lines are arranged on the moving body in the longitudinal direction. In a method in which a plurality of antennas are mounted, the antenna receives the high frequency magnetic field, and the received voltage is processed, the relative position of the moving object is continuously detected on the moving object at a constant period. The frequency and a high-frequency current of a second frequency obtained by doubling this are superimposed to energize the guided radio line, and on the moving body, two The high frequency magnetic field is received by an antenna, and the first of the received voltages of each of the antennas is
Determine the absolute value of the envelope of each antenna reception voltage based on the frequency component or the second frequency component, double the first frequency component of each antenna reception voltage, and calculate the reference phase signal of the second frequency from the logical sum. seek,
By comparing the phase of the second frequency component of each of the antenna reception voltages and the reference phase signal, it is determined whether the sign of the envelope of each of the antenna reception voltages is positive or negative, and each of the antennas in which the sign of the sign is determined is positive or negative. From the received voltage envelopes Vae and Vbe, the moving object position z is continuously detected at a period P using the following formula: Z=-P/2πtan -1 Vbe/Vae.
In addition, if there are three or more antennas, the P/N
The high-frequency magnetic field is received by N antennas (N≧3) arranged at intervals of determining the absolute value of the line, and doubling the first frequency component of at least two of the voltages received by each antenna;
A reference phase signal of a second frequency is obtained from the logical sum, and the phase of the second frequency component of each antenna reception voltage and the reference phase signal is compared to determine whether the sign of the envelope of each antenna reception voltage is positive or negative. and the envelope Vie (i=1, 2, 3...N) of each antenna reception voltage whose sign is determined
From, the moving body position z can be calculated using the following formula Therefore, the detection is performed continuously at a period P. The case using two antennas will be explained in detail below. In the present invention, the reception voltages Va and Vb of two antennas are
The phase angle of the positive phase voltage Vp or the negative phase voltage Vn is calculated digitally based on the value of the envelope of . The positive sequence voltage Vp of the antenna reception voltages Va and Vb is,
As is clear from the above explanation, it is also expressed by the following equation. Vp＝k・e j(2 〓 /P)z- 〓 zj 〓 z+j 〓 t ＝Va＋e -
j・Vb＝Va−jVb……(5) Letting the envelopes of Va and Vb be Vae and Vbe, respectively,
Equation (5) can be expressed as the following equation. Va=Vae・e -j 〓 z+j 〓 t Vb=Vbe・e -j 〓 z+j 〓 t ...(6) From equations (1) and (6), Vae=k・e - 〓 z・cos2π/Pz Vbe=k・e - 〓 z・cos(2π/Pz+π/2)……(7
) becomes. These quantities are real numbers (positive or negative quantities). By separating Vp into multiple vectors vp representing steady-state electrical quantities and phase quantities, it can be expressed as Vp=vp・e -j 〓 z+j 〓 t ……(8). From equations (5), (7), and (8), vp=k・e − 〓 z・e j(2 〓 /P)z = Vae−jVbe ……(9) is obtained. Therefore, ∠vp=(2π/P)z=−tan -1 (Vbe/Vae)...(1
0) is obtained. By this, if we can know the magnitude and sign (positive or negative) of Vae and Vbe, ∠
You can know the value of vp. In this case, z is P
Every time ∠vp increases, ∠vp shows an increase of 2π, and ∠vp
It becomes possible to continuously detect the moving body position z with a period P through the value of . By the way, normally on a moving body, the envelopes Vae and Vbe
Although it is extremely easy to know the amplitude of these quantities, it is impossible to determine whether these quantities are positive or negative because there is no reference phase signal that serves as a basis for determining these signs. Therefore, in the present invention, the transmission frequency from the ground transmitter to the guided radio line is two frequencies, the first and second frequencies, and the second frequency of these two frequencies is twice the first frequency. These are selectively received by an antenna on the body, and the first frequency is further doubled and used as a reference phase signal to determine whether the envelope of the received voltage detected at the second frequency is positive or negative. If the first frequency ω ₁ components of the received voltages Va and Vb at the two antennas are expressed as Va (ω ₁ ) and Vb (ω ₁ ), respectively, then Va (ω ₁ )=k ₁・cos2π/Pz・e−α ₁ z−jβ ₁ z＋jω ₁
t Vb(ω ₁ )=k ₁・cos2π/P(z+1/4P)・e−α ₁
The following relationship is obtained: z−jβ ₁ z+jω ₁ t ...(11). Similarly for the second frequency ω ₂ component, Va(ω ₂ )=k ₂・cos2π/Pz ・e−α ₂ z −jβ ₂ z+j
ω ₂ t Vb (ω ₂ )=k ₂・cos2π/P(z+1/4P)・e−α ₂
The following relationship is obtained: z−jβ ₂ z+jω ₂ t ...(12). Here, the subscripts 1 and 2 attached to k, α, and β mean quantities related to frequencies ω ₁ and ω ₂ , respectively. Va(ω ₁ )=Vae(ω ₁ )・e−jβ ₁ z+jω ₁ t Vb(ω ₁ )=Vbe(ω ₁ )・e−jβ ₁ z+jω ₁ t …(13), Vae(ω ₁ ), Vbe(ω ₁ ) is called an envelope, then Vae(ω ₁ )=k ₁・e−α ₁ z ・cos2π/Pz Vbe(ω ₁ )=k ₁・e−α ₁ z ・cos(2π/Pz+π/2)...(14) These quantities are real numbers (positive or negative quantities), and their absolute values represent the amplitudes of Va (ω ₁ ) and Vb (ω ₁ ), respectively. Also, the positive and negative values of Vae (ω ₁ ) and Vbe (ω ₁ ) are respectively
cos(2π/P)z, cos[(2π/P)z+(π/2)]
matches that of On the other hand, if the instantaneous phase angle values of Va (ω ₁ ) and Vb (ω ₁ ) are respectively ∠Va (ω ₁ ) and ∠Vb (ω ₁ ), then these are
From equation (13), it can be written as follows. ∠Va(ω ₁ )=−β ₁ z+ω ₁ t(Vae(ω ₁ )>0)=π−
β ₁ z + ω ₁ t (Vae (ω ₁ ) < 0) ∠Vb (ω ₁ ) = − β ₁ z + ω ₁ t (Vbe (ω ₁ ) > 0) = π−
β ₁ z + ω ₁ t (Vbe (ω ₁ ) < 0)...(15) Furthermore, the values obtained by multiplying Va (ω ₁ ) and Vb (ω ₁ ) by 2 are Vaw (ω ₁ ) and Vbw (ω ₁ ), respectively. and the instantaneous values of the phase angles are Vaw (ω ₁ ) and ∠Vbw (ω ₁ ), respectively. Regardless of whether Vaw (ω ₁ ) or Vbw (ω ₁ ) are positive or negative, they are as follows. I can write. ∠Vaw (ω ₁ ) = ∠Vbw (ω ₁ ) = −2β ₁ z + 2ω ₁ t……(16) In addition, the instantaneous phase angle values of Va (ω ₂ ) and Vb (ω ₂ ) are respectively expressed as ∠Va (ω ₂ ), ∠Vb(ω ₂ ), ∠Va(ω ₂ )=−β ₂ z+ω ₂ t(Vae(ω ₂ )>0)=π−
β ₂ z + ω ₂ t (Vae (ω ₂ ) < 0) ∠Vb (ω ₂ ) = − β ₂ z + ω ₂ t (Vbe (ω ₂ ) > 0) = π-
β ₂ z + ω ₂ t (Vbe (ω ₂ ) < 0) (17). If the phase difference between ∠Va (ω ₂ ) and ∠Vaw (ω ₁ ) is △φa, then cos(2π/P)z>0(Vae(ω ₁ ), Vae
(ω ₂ ) are both positive), from equations (16) and (17), △φa = ∠Va (ω ₂ ) − ∠Vaw (ω ₁ ) = (−β ₂ z + ω ₂ t)
−(−2β ₁ z+ω ₁ t)=(2β ₁ +β ₂ )z=δ……(18). Here, δ is a quantity defined by δ=(2β ₁ −β ₂ )z (19). Also, cos(2π/P)
Similarly, when z<0 (both Vae(ω ₁ ) and Vae(ω ₂ ) are negative), △φa=∠Va(ω ₂ )−∠Vaw(ω ₁ )=(π−β ₂ z+ω ₂ t
)−(−2β ₁ z+2ω ₁ t)=π−(2β ₁ +β ₂ )z=π−
δ...(20) is obtained. In the guided radio frequency band (50-200kHz),
Since the phase constant of the guided radio line is approximately proportional to the frequency, the value of δ is often extremely small. now,
Ignoring this quantity for simplicity, equations (18) and (20)
The formulas are respectively △φa=0(cos(2π/P)z>0)=π(c
It is clear that os(2π/P)z<0)...(21). In this way, by determining whether the phase of △φa is 0 or π, the sign of cos(2π/P)z (in other words, the sign of Vae(ω ₁ ) and Vae(ω ₂ )) can be easily determined. can be determined. The case where the guided radio line length is extremely long and the influence of δ cannot necessarily be ignored is as follows. If the total length of the guided radio line is L, |δ| becomes maximum when z=L, and this value is |δ
When expressed as |max, |δ|max=(2β ₁ −β ₂ )L (22). From equations (18), (20), and (22), cos(2π/
P) z＞0(If Vae(ω ₁ ) and Vae(ω ₂ ) are both positive, −|δ|max<△φa<+|δ|max...(23) cos(2π/P)z >0 (if Vae(ω ₁ ) and Vae(ω ₂ ) are both negative, π−|δ|max<△φa<π+|δ|max
...(24) becomes. Since the value of |δ|max is relatively small, |δ|
By setting max=π/2, all cases can be dealt with. Using this value, cos(2π/P)z>0(Vae
(ω ₁ ) and Vae (ω ₂ ) are both positive), −(π/2)<△φa<π/2 ...(25) cos(2π/P)z>0(Vae(ω ₁ ), Vae (ω ₂ ) are both negative), then π/2<△φa<3π/2...(26) In other words, the value of △φa is expressed by equations (25) and (26).
By determining in which range of the expression the envelopes Vae(ω ₁ ) and Vae(ω ₂ ) are positive or negative (sign), it is possible to know the sign. Furthermore, the positive and negative (signs) of the envelopes Vbe (ω ₁ ) and Vbe (ω ₂ ) can be found in a similar manner. In this way, if we can know the absolute value and sign of the received voltage envelope of each antenna, then ∠
vp=2π/Pz=−tan -1 Vbe(ω ₁ )/Vae(ω ₁ )……(
27) Or, z=-P/2π=tan -1 Vbe(ω ₁ )/Vae(ω ₁ )……(28
), the moving body position z can be detected continuously with a period P. [Example] Hereinafter, an example of the present invention will be described in detail with reference to FIGS. 1 to 4. FIG. 1 is an overall explanatory diagram of an embodiment of the present invention. Note that parts with the same names and functions as those in FIG. 5 are given the same reference numerals. 7 is the output of the antennas 2a and 2b (Va, respectively
This is a signal processing circuit that processes the signal Vb) and calculates the moving body position z by digital calculation, and its internal configuration is shown in FIG. 8 is a signal generator that outputs a continuous sine wave of frequency ω ₁ ; 9 is a signal generator that doubles the signal of frequency ω ₁ , converts it into a continuous sine wave of frequency ω ₂ (ω ₂ = ω ₁ × 2), and outputs it. 2 multiplier circuits, 10 ₁ and 10 ₂ are transmitters for power amplifying continuous sine waves of frequencies ω ₁ and ω ₂ , respectively; 11;
is a multiplexer that combines the outputs of the transmitters 10 ₁ and 10 ₂ and outputs a signal toward the guided radio line 4. In this configuration, the signals of frequencies ω ₁ and ω ₂ output from the signal generator 8 are divided into two, one being sent to the transmitter (power amplifier) 10 ₁ and the other being sent to the transmitter (power amplifier) 10 1 via the doubling circuit 9. power amplifier) 10 ₂ respectively. Transmitter 10 ₁ output (frequency ω ₁ ) and transmitter 1
0 ₂ output (frequency ω ₂ ) is combined by a multiplexer and then supplied to the guided radio line 4. These signals propagate along the guided radio line 4 and are received by the antennas 2a and 2b mounted on the mobile body. FIG. 3 shows an example of the signal processing circuit 7 in detail. 12a and 12b are buffer amplifiers that convert the outputs Va and Vb of the antennas 2a and 2b, respectively, into unbalanced voltages;
13a and 13b are band pass filters (hereinafter referred to as "BPF") each having the frequency ω ₁ as the center frequency of the passband, and 14a and 14b are BPFs each having the frequency ω ₂ as the center frequency of the passband. 15a, 15
b is a linear detector that outputs a DC voltage that is exactly proportional to the high frequency voltage input to it; 16a, 16;
Reference numerals b, 16c, and 16d are waveform shapers that change the high-frequency signals input thereto into rectangular waves having the same frequency and phase as the rectangular waves, and output the rectangular waves. 17a, 17b
18 is a doubling circuit that doubles the output of the waveform shapers 16c and 16d, and 17 is a doubling circuit 17a, 17.
20a and 20b are waveform shapers, respectively. This is a phase comparator that compares the phases of the outputs of 16a and 16b with the reference phase signal from the OR circuit 18. 21 is an arithmetic control unit, which includes an input interface 21a that incorporates various data input from the outside, a ROM 21b that stores a processing program for the input data, a CPU 21c that processes the input data according to the program in the ROM 21b,
RAM 21 that temporarily stores the intermediate data
d, and an output interface 21e for outputting data processing results to the outside. The received voltages Va and Vb of the antennas 2a and 2b are converted into unbalanced voltages by buffer amplifiers 12a and 12b, respectively. Received voltage Va of antennas 2a and 2b,
Vb is a balanced voltage caused by induction,
On the other hand, since the circuit elements (amplifiers, logic circuits, transistors, etc.) used in the signal processing circuit 7 connected to the antennas 2a and 2b are of the earth return type (Earth Return, that is, unbalanced type),
In order to rationally process the antenna reception voltages Va and Vb in the signal circuit 7, it is necessary to provide the interference amplifiers 12a and 12b, which are balanced-unbalanced conversion circuit elements, at the first stage of the signal processing circuit 7. The output from buffer amplifiers 12a and 12b is BPF
13a, 14a and 13b, 14b. Among these, components Va (ω _{1 )} and Vb (ω ₁ ) of frequency ω 1 are divided into two after passing through BPFs 13a and 13b, respectively, and one is inputted to linear detectors 15a and 15b, where |Va (ω ₁ )| , |Vb(ω ₁ )| (i.e. |Vae(ω ₁
)
|, |Vbe(ω ₁ )|, and AD converter 19a, 1
9b converts it into a digital quantity and then inputs it to the input interface 21a.The other inputs it to the waveform shapers 16c and 16d, converts it into a rectangular wave with the same frequency and the same phase, and then sends it to the doubling circuits 17a and 1.
In step 7b, the signal is multiplied by two, and placed in an OR circuit 18, where the logical sum of the two is calculated. double multiplier circuit 17a,
The repetition frequency and phase of the rectangular wave pulse train output from 17b are Vaw (ω ₁ ), Vbw
(ω ₁ ). Also, Vaw (ω ₁ ), Vbw
The magnitude of (ω ₁ ) changes depending on the moving body position z and becomes zero alternately, so that the waveform shapers 16c and 16d
, and the outputs of the doubler circuits 17a and 17b are alternately zero, but the OR circuit 18 calculates the logical sum of the two, and a constant amplitude rectangular wave with a repetition frequency of _2ω1 is obtained. The output of the OR circuit 18 is input to the phase comparators 20a and 20b and functions as a reference phase signal. Among antennas 2a and 2b receiving voltages Va and Vb,
The components Va (ω ₂ ) and Vb (ω ₂ ) of frequency ω ₂ are respectively
Waveform shaper 16 passes through BPF14a, 14b
a, 16b, respectively Va (ω ₂ ), Vb
It is converted into a rectangular wave having the same repetition frequency and the same phase as (ω ₂ ), and is input to the phase comparators 20a and 20b. When δ=0, the output waveforms of the waveform shaper 16a are shown in FIGS. 4a and 4b, and the output waveform (reference phase signal) of the OR circuit 18 is shown in FIG. 4c. It is easy to understand that the relationship in equation (21) holds.
In the phase comparators 20a and 20b, the aforementioned reference phase signal (frequency 2ω ₁ ) and the waveform shaper 16a,
A phase comparison is performed with the output of 16b (frequency ω ₂ ), but since ω ₂ was originally obtained by doubling ω ₁ , 2ω ₁ and ω ₂ always match exactly; The above-mentioned phase comparison becomes possible. Input interface 21a of calculation control unit 21
As mentioned above, the AD converters 19a and 19b are
In addition to the outputs of the phase comparators 20a and 20b (respectively |Vae(ω ₁ )|, |Vbe(ω ₁ )|), the outputs of the phase comparators 20a and 20b (respectively φa,
△φb) is input. In the arithmetic control section 21, processing of these force data is started based on the program stored in the ROM 21b. First, from the values of △φa and △φb, Vae (ω ₁ ) and Vbe
(ω ₁ ) is determined to be positive or negative, and the result and |Vae(ω ₂ )
By combining the values of | and |Vbe(ω ₂ )|, Vae(ω ₁ ) and Vbe(ω ₁ ) can be specified as algebraic quantities. Subsequently, the phase angle ∠vp is directly calculated digitally using equation (27) or equation (28), and through this, the moving body position z can be continuously detected with a period P. In other words, as shown in Fig. 2, ∠vp increases by 2π every time z increases by P, and the moving object position z can be continuously detected with a period P through the value of ∠vp. . In the signal processing circuit shown in Fig. 3, the absolute value of the envelope of the antenna reception voltage is |Vae(ω ₁ )|,
|Vbe(ω ₁ )| is used, but instead of |
Exactly the same result can be obtained using Vae(ω ₂ )| and |Vbe(ω ₂ )|. Alternatively, the phase angle ∠vn of the negative phase voltage may be calculated, and the moving body position z may be determined through this. Although the above embodiments have been described with reference to two antennas, the present invention is also applicable to three or more antennas. Next, a case where there are three antennas will be explained.
If three antennas are installed at intervals of P/3 and the received voltages are Va, Vb, and Vc, respectively, the following relationship holds between these voltages and the moving body position z. Va=k cos(2πz/P)・e - 〓 zj 〓 z+j 〓 t Vb=k cos {2π(z+P/3)/P}・e - 〓 zj 〓 z+j
〓 t = k cos(2πz/P+2π/3)・e - 〓 zj 〓 z+j 〓 t
Vc=k cos {2π(z+2P/3)/P}・e - 〓 zj 〓 z+j
〓 t = k cos (2πz/P+4π/3)・e - 〓 zj 〓 z+j 〓 t
=k cos(2πz/P−2π/3)・e - 〓 zj 〓 z+j 〓 t
...(28-1) k is a constant, α and β are the attenuation constant and phase constant of the guided radio line, respectively. The above equation (28-1) is transformed as follows. Va=1/2k(e j2 〓 z/P +e -j2 〓 z/P )・e - 〓 zj 〓 z+j
〓 t Vb=1/2k(e j2 〓 z/P+j2 〓 /3 +e -j2 〓 z/P
+j2 〓 /3 )・e - 〓 zj 〓 z+j 〓 t Vc=1/2k(e j2 〓 z/P-j2 〓 /3 +e -j2 〓 z/P
+j2 〓 /3 )・e - 〓 zj 〓 z+j 〓 t ...(28−2) Here, the positive sequence voltages Vp and Vn are defined as in the following equations. Vp＝Va＋e -j2 〓 /3・Vb＋e j2 〓 /3・Vc Vn＝Va＋e -j2 〓 /3・Vb＋e -j2 〓 /3・Vc……(29) Expression (28-2) is By substituting into equation 1, we get
Vp is as follows. Vp=1/2k(e j2 〓 z/P +e -j2 〓 z/P +e j2 〓 z/P+j2 〓 /3
-j2 〓 /3 +e -j2 〓 z/P-j2 〓 /3-j2 〓 /3 +e j2 〓 z/P-j2 〓 /3+j2 〓 /3 +e -j2 〓 z/P+j2 〓 /3 +j2 〓 /
3 )・e - 〓 zj 〓 z+j 〓 t = 1/2k {(3e j2 〓 z/P +e -j2 〓 z/P (1+e -j4 〓 /3
+e j4 〓 /3 )｝・e - 〓 zj 〓 z+j 〓 t = 3/2ke j2 〓 z/P- 〓
zj 〓 z+j 〓 t (∵e -j4 〓 /3 =e j2 〓 /3 , e j4 〓 /3 =e -j2 〓 /3 , 1+e j
2 〓 /3 +e -j2 〓 /3 = 0)... (29-1) When expressed separately into the complex vector vp representing the steady state electrical quantity and the phase quantity, the following equation is obtained. Vp=vp・e -j 〓 z+j 〓 t ……(30) However, Vp=3/2ke − 〓 z・e j2 〓 z/P ……(30−1). On the other hand, for Va, Vb, and VC, formula (28-1)
If it is expressed separately into the envelopes Vae, Vbe, VCe and the phase amount, the following equation is obtained. Va＝Vae・e -j 〓 z+j 〓 t Vb＝Vbe・e -j 〓 z+j 〓 t Vc＝Vce・e -j 〓 z+j 〓 t ……(31) However, the envelope Vae, Vbe, Vce are Vae=k cos (2πz/P)・e - 〓 z Vbe=k cos (2πz/P+2π/3)・e - 〓 z Vce=k cos (2πz/P−2π/3)・e - 〓 z
...(31-1). If we rewrite the first equation of equation (29) using (30), (30-1), and (31), we get Vp=vp・e -j 〓 z+j 〓 t =3/2ke - 〓 z・e j2 〓 z/P・e -j 〓
z+j 〓 t = (Vae+e -j2 〓 /3・Vbe+e j2 〓 /3・Vce)・e -j
〓 z+j 〓 t
...(31-2) Immediately from this, vp=3/2ke - 〓 z・e j2 〓 z/P = Vae+(-1/2-j√
3/2) Vbe+(-1/2-j√3/2)Vce = {Vac-1/2(Vbe+Vce)}-j√3/2(Vbe-
Vce)...(31-3) If the argument angles (phase angles) on both sides of the above equation are set equal, ∠vp=2πz/P=tan -1 −√3/2(Vbe−Vce)/Vae−
1/2 (Vbe−Vce)
...(32) In other words, if the real and imaginary parts of the positive sequence voltage vector are known, the argument of the same voltage becomes clear,
The moving object position z can be determined. Similar calculations can also be performed using reverse phase voltages. Generally, when there are N antennas (N≧3),
The interval between these antennas is P/N, and the envelope of each antenna reception voltage is Vie (i=1, 2, 3
...N), the moving body position z is It can be found from [Effects of the Invention] As explained above, the position detection method of the present invention uses a guided radio line formed of a corrugated reciprocating conductor with a constant period P, which is laid along a moving vehicle travel path, at a frequency ω. By applying a current with a frequency of ω ₁ and ω ₂ multiplied by 2, a high-frequency magnetic field that is distributed in a sinusoidal manner in the longitudinal direction of the guided radio line is formed, and even if multiple antennas are installed at regular intervals on a moving body, Then, the high-frequency magnetic field is selectively received for each frequency, the amplitude of the envelope of the induced voltage of each antenna is determined, and the standard is determined from the voltage obtained by doubling the ω ₁ component of the induced voltage of each antenna. The phase voltage is used as a reference to determine whether the envelope of each antenna induced voltage is positive or negative, and the position of the moving object is measured periodically and continuously based on these values. It is now possible to measure continuously at intervals of Therefore, the conductor period P can be shortened for a given detection period, and costs can be reduced by improving conductor installation accuracy and facilitating manufacturing. Further, by making the on-vehicle antenna smaller, it becomes easier to mount the antenna.}

[Brief explanation of drawings]

FIG. 1 is an overall explanatory diagram of one embodiment of the present invention, and FIG.
The figure is an explanatory diagram of the relationship between the position of the moving body and the positive-sequence voltage phase angle, Fig. 3 is an explanatory diagram of an example of a signal processing circuit, and Fig.
The figure is an explanatory diagram of the relationship between the phase of the ω ₂ component of the received voltage and the reference phase signal. Figure 5 is an explanatory diagram of the conventional example.
The figure is an explanatory diagram of the relationship between the position of a moving body and the phase angle in a conventional example. 1a, 1b: conductor, 2a, 2b: antenna,
4: Guided radio line, 3, 7: Signal processing circuit, 8:
Signal generator, 9: double multiplier circuit, 10 ₁ , 10 ₂ : ground transmitter, 11: multiplexer, 12a, 12b: buffer amplifier, 13a, 13b, 14a, 14b:
BPF, 15a, 15b: Linear detector, 16a,
16b, 16c, 16d: waveform shaper, 17a,
17b: double multiplier circuit, 18: OR circuit, 19a,
19b: AD converter, 20a, 20b: phase comparator, 21: calculation control unit.

Claims (1)

[Scope of Claims] 1. A guided radio line in which reciprocating conductors bent into a waveform shape at a constant period P are shifted by P/3 in the longitudinal direction of the track is laid along the travel path of a moving object, and this A high frequency magnetic field distributed in a sinusoidal manner in the longitudinal direction of the guided radio line is formed by applying a high frequency current to the guided radio line, and a plurality of antennas arranged in the longitudinal direction of the guided radio line are mounted on a moving body,
In a method of continuously detecting the relative position of a moving body on a moving body at a constant period by receiving the high frequency magnetic field by the antenna and processing the received voltage, the first frequency and the second frequency are doubled. The high-frequency current of the second frequency obtained is superimposed and energized through the guided radio line, and on the moving body, the high-frequency magnetic field is received by two antennas arranged at an interval of P/4. ,
The absolute value of the envelope of each antenna reception voltage is determined based on the first frequency component or the second frequency component of the reception voltage of each antenna, the first frequency component of each antenna reception voltage is multiplied by 2, and the logical sum thereof is calculated. A reference phase signal of a second frequency is obtained from , and the phase of the second frequency component of each of the antenna reception voltages and the reference phase signal is compared to determine whether the sign of the envelope of each of the antenna reception voltages is positive or negative. , the envelope of each antenna reception voltage whose sign is determined to be positive or negative;
A moving body position detection method characterized in that the moving body position z is continuously detected at a period P from Vae and Vbe using the following formula: Z=-P/2πtan ^-1 Vbe/Vae. 2. An inductive radio line consisting of reciprocating conductors bent into a waveform at a constant period P and shifted by P/3 in the longitudinal direction of the line is laid along the travel path of the moving object, and a high-frequency current is applied to it. thereby forming a high frequency magnetic field distributed in a sinusoidal manner in the longitudinal direction of the guided radio line, and mounting a plurality of antennas arranged in the longitudinal direction of the guided radio line on the moving body,
In a method of continuously detecting the relative position of a moving body on a moving body at a constant period by receiving the high frequency magnetic field by the antenna and processing the received voltage, the first frequency and the second frequency are doubled. The high-frequency current of the second frequency obtained is superimposed and energized through the inductive radio line, and on the moving body, N antennas (N≧3) arranged at intervals of P/N are used to superimpose the high-frequency current of the second frequency obtained. A high frequency magnetic field is received, the absolute value of the envelope of each antenna reception voltage is determined based on the first frequency component or the second frequency component of the reception voltage of each antenna, and the absolute value of the envelope of the reception voltage of each antenna is determined. By doubling the first frequency component, calculating the reference phase signal of the second frequency from the logical sum, and comparing the phase of the second frequency component of each of the antenna reception voltages and the reference phase signal, each of the antennas It is determined whether the sign of the envelope of the received voltage is positive or negative, and the envelope Vie(i
= 1, 2, 3...N), the moving body position z can be calculated using the following formula. A moving body position detection method characterized in that continuous detection is performed at a period P.