JPH06331733A - Method and equipment for measuring distance - Google Patents

Abstract

PURPOSE:To allow online operational measurement by shortening the time of corrective operation for determining a highly accurate distance value through correlation of measured distance values and shift measured values. CONSTITUTION:A measured distance value up to a target E is determined by receiving a repetitive pulse wave transmitted from a distance measuring section 1 at a predetermined period. The measured distance value is determined based on the time to be elapsed between a specified point of a transmission pulse wave and a specified point of a receiving pulse wave. Measured shift amount is determined every moment at the position of a target E by transmitting a continuous wave at a predetermined frequency from a shift measuring section 2. The measured shift amount is determined based on the difference between transmission frequency and receiving frequency. A corrective distance value operating section 3 solves an equation Rc='R(i)'='R(0, i)'+r(i); where, R(0) is an initial measured distance value, R(i) is every time measured distance value, r(i) is every time measurement shift value, Rc is corrected distance value, and 'R(0,i)' is an estimated measured distance value for minimizing the square sum of error. Since the method of sequential least squares is used for convergence long operation, e.g. equation of Kalman filter, is not required thus shortening the operating time significantly.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tracking type distance measuring method using a combination of distance measurement by reflection detection and displacement measurement by the Doppler effect, and a distance measuring device using this method. In addition, in the numerical values or operation symbols of the present invention, a symbol preceded by * indicates that the symbol represents a vector, a symbol enclosed by “” indicates an estimated value, and a superscript symbol. T represents transposition. The symbol i is 1, 2, 3, ...
... is a symbol representing N and represents the order of the obtained times, for example, how many times the measured value is.

[0002]

2. Description of the Related Art As a distance measurement by reflection detection, a reflected wave of a transmission wave that repeats periodically is obtained, and an elapsed time from a specified point of each cycle of the transmitted wave to a specified point of each cycle of the reflected wave, for example, A pulse reflection type distance measuring device that measures the distance from the detection point to the target based on the elapsed time from the transmitted pulse wave to the received pulse wave is well known, and such a pulse reflection type distance measuring device is a laser. And radar using electromagnetic waves, and fish finder and distance measuring device using ultrasonic waves.

As a displacement amount measurement by the Doppler effect, a velocity measuring device / displacement using electromagnetic waves or ultrasonic waves, which measures the moving velocity / moving amount of a target based on the frequency varying amount of a reflected wave with respect to a constant frequency transmission wave There is a quantity measuring device. Such speed measuring devices and displacement amount measuring devices include those that use a continuous wave as a transmission wave and those that use a pulse wave obtained by pulse-modulating a carrier wave.

In a target tracking using a radar, that is, in a tracker, an α-β tracker for improving tracking accuracy by engaging a position smoothing constant α and a velocity smoothing constant β, and an optimal estimation theory by a Kalman filter in such a tracker. There is a tracking filter configuration that performs tracking by an operation that applies .alpha., And α that also considers the target speed change amount γ
The fact that-[beta]-[gamma] trackers have been studied is disclosed in "Electronic Communication Handbook", March 28, 1979, Vol. 28, No. 1, Section 5 (Radar Information Processing).

As a frequency discriminating circuit for detecting a frequency change amount or a phase change amount, a quadrature type frequency discriminating circuit for multiplying a quadrature phase signal is described in the second volume of the tenth edition of the above-mentioned document.
It is disclosed in department 3 (angle modulation).

In the Kalman filter, the measurement using the method of converging to a constant value by the Riccati type equation is disclosed in the 5th volume, 1st section 2 (filtering and prediction) of the above-mentioned document.

In the pulse reflection type distance measurement, as shown in FIG. 10, the time ta from the specified point a of the transmitted pulse wave A to the specified point b of the received pulse wave B is measured, and this time ta and the propagation speed of the pulse wave are measured. The measured distance value R is obtained from the product with c. In this measurement, the time lapse from the transmission to the reception of the reflected wave is mainly measured, so the measured value can be obtained only intermittently.

Further, as shown in FIG. 11, the waveform of the received pulse wave B is affected by the propagation path of the pulse wave traveling back and forth between the detection point and the target, the reflecting surface of the target, noise, etc. Since the waveform of the transmission pulse wave A is irregularly deformed,
The measured distance value R inevitably includes an irregular error because the position of the defined point b also changes irregularly. When the measured distance value R (i) is plotted every time, 12
As described above, since the error values are not constant, they are dispersed.

In the Doppler shift amount measurement, as shown in FIG. 13, a transmission wave C of a continuous wave having a frequency fo is generated by the Doppler effect generated by the moving speed S of the target, so that the frequency f
Since the received wave D shifts to s, the amount of change in frequency or phase detected by comparing the frequency fs with the frequency fo is Δ
Moving speed S and time tb obtained by measuring f or Δp
The moving distance value, that is, the measured displacement amount r is calculated from In this measurement, since the frequency change is mainly measured, the measurement value is continuously obtained, and relatively high measurement accuracy is obtained, and the distance value R (0) at the first measurement point is known. If so, the accumulated distance value obtained by accumulating the measured displacement amount r (i) at each time is plotted, and FIG.
As described above, there is an advantage that it can be obtained in a linear form with a small error value.

[0010]

In the course of plotting the integrated distance as described above, the measured displacement r (i) is disturbed or interrupted by the passage of the transmitted wave by an object other than the target object. And a large amount of error value in the integrated distance value due to the movement amount due to the disturbance or interruption,
This causes the inconvenience that measurement becomes substantially impossible.

Therefore, a method of engaging the pulse reflection type distance measurement and the Doppler shift amount measurement and applying the optimum estimation theory to calculate the measured distance value is extremely effective.

However, in the conventional method of applying the optimum estimation theory, it takes too long time for the convergence in the calculation for the optimum estimation, and in such tracking type distance measurement, the velocity change of the moving body is changed. If the speed is high or if the movement data is to be obtained in detail, the calculation of the integrated distance value cannot be completed in time, and the purpose cannot be achieved.

Therefore, there is a problem that it is desired to provide a distance measuring method and a distance measuring device which do not have such inconvenience.

[0014]

According to the present invention, the pulse reflection type distance measurement and the Doppler shift amount measurement as described above are engaged with each other, and the optimum estimation theory is applied to converge the measurement distance value. In the distance measuring method, the convergence time is calculated by the recursive least squares method so that the calculation time can be shortened and the above problems can be solved.

[0015]

Although the calculation method of the optimal estimation theory and the equation in the Kalman filter must solve a very long multiple calculation expression, the expansion of the calculation expression in the case of the convergence calculation by the recursive least squares method is much shorter and the single stroke The calculation time can be extremely shortened because it can be performed by the calculation of, and the online configuration can also be used for tracking when the speed change of the moving body is fast or when it is necessary to obtain detailed movement data. You can

[0016]

【Example】

[First Embodiment] A first embodiment will be described below with reference to FIGS. In FIGS. 1 to 4, portions indicated by the same reference numerals as those in FIGS. 10 to 13 have the same functions as the portions having the same reference numerals described in FIGS. 10 to 13.

In FIG. 1, the distance measuring unit 1 is shown in FIG.
As shown in FIG. 11, a transmission pulse wave A of a radio wave is transmitted, a reception pulse wave B reflected from a target E is received, and a predetermined point a to a predetermined point b of both pulse waves is received. Is a part of measuring the time ta of and obtaining the amount of time ta (i) corresponding to the measured distance value R (i) every time. Since the transmission pulse A is repeatedly transmitted periodically, the time amount ta
In summary, (i) is from the defined point a of the transmission pulse A, that is, the defined point of each cycle of the transmitted wave, to the defined point b of the received pulse B, that is, the defined point of the transmitted wave in each cycle of the reflected wave. You have gained the amount of time to the corresponding regulatory point.

As shown in FIG. 13, the displacement measuring section 2 transmits a transmission wave C having a frequency fo, receives a reception wave pulse D reflected from the target E, and moves at a moving speed S ( (+ S when moving away from the measurement point and -S when approaching the measurement point) measures the same period point of the waveform of the frequency fs of the received wave D, which is deviated by, for example, the time amount tc between the zero cross points of the waveform. By doing so, the frequency fs is measured from the reciprocal thereof, and the frequency change amount fs (i) corresponding to the measurement change amount r (i) every time (when the frequency change amount is a minute change, the phase change amount is measured). However, in this embodiment, the amount of phase change in such a case is called the amount of frequency change.)
Is the part to get.

The distance measuring unit 1 and the displacement measuring unit 2 form an analog processing unit that processes each measurement in an analog manner.

The corrected distance value calculation unit 3 is a unit for A / D converting the analog measurement values obtained by the distance measurement unit 1 and the displacement measurement unit 2 to perform the required digital processing. , And has a distance value measuring means, and this means obtains a measured distance value R (i) for each time by the product of the time amount ta (i) for each time obtained by the distance measuring unit 1 and the propagation velocity c of the radio wave. The measurement is performed for.

Secondly, it has a displacement amount measuring means,
According to this means, the frequency shift amount fs (i) obtained each time by the shift amount measuring unit 2 is based on the propagation speed c of the radio wave, and the frequency shift due to the Doppler effect is

[Equation 1] Since it is related by

[Equation 2] The calculation of the moving speed S is performed, the frequency fs is sampled, the above calculation is performed, and a product of the frequency fs and the time tb until the next sampling is performed to obtain the measured displacement amount r (i) every time. It is a thing.

Thirdly, it has an optimum estimation calculation means, which means an initial measured distance value R (0) obtained by the distance measuring means at a predetermined time point and, after this predetermined time point,
Measured distance value R obtained by the distance measuring means every time
On the basis of (i) and the measured displacement amount r (i) obtained by the displacement amount measuring means each time, the calculation process of the optimal estimation by the Kalman filter is performed, but the process of the calculation process is replaced by the Riccati type dispersion equation. , An operation for performing convergence by the recursive least squares method is used.

That is, the coefficient is α, α ≠ 1, and the error value is ε.
Equation (i)

[Equation 3] And an equation for calculating the estimated value “R (0,1)” of R (0) that minimizes the sum of squares of the error value ε (i)

[Equation 4] The estimated value “R (i)” calculated by setting
As c, that is,

[Equation 5] A means for obtaining the corrected distance value Rc is provided.

The processing for performing each of the above means is performed by an arithmetic processor (C in the present invention) provided in the corrected distance value arithmetic unit 3.
(PU) and required constant values, coefficient values, etc. are stored in advance in the CPU.

The display unit 4 displays the corrected distance value R (N) obtained by the corrected distance value calculation unit 3 and the elapsed measurement time on a numerical display, or converts each of these values into an analog value. Is a part for plotting and displaying on the screen.

FIG. 2 shows an error value ε at the initial measured distance value R (0) when the convergence of measured values is shown by a figure when the display unit 4 is displayed by plotting analog values.
_R (0) gradually decreases according to the integrated value of the measurement displacement amount r (i) each time, and the corrected distance value R (i) converges to the true distance value R _T (i) each time. The distance measurement accuracy is improved.

The above predetermined time point is the measurement start time point, and the reflected wave other than the target object is the transmission wave for obtaining the respective measured values of the measured displacement amount r (i) and the measured distance value R (i). Detection to set an abnormal measurement value that is interrupted by the measurement, or when the measurement value is no longer available and that the measurement value is close to a predictable measurement value when the measurement value is restored. As shown in FIG. 3, by providing the corrected distance value calculation unit 3 with the function of performing calculation processing of each measured value,
Similarly, the distance measurement accuracy can be improved by starting the measurement at the point of time when the measurement is restored.

In the case of FIG. 3, the above abnormal time is treated as a data loss, and the integrated value obtained by accumulating the corrected distance value R (N) and the measured displacement amount r (i) during this period is set as the value before the data loss. I keep it and consider it to have not changed,
Even if the data in the data-missing portion is reset to zero and measured, the progress after the data restoration is substantially the same. In some cases, it may be possible to make an extension trajectory by estimating the value as the movement data before the data loss, but if the movement is made in the opposite direction during this time, the error becomes rather large. When i) is obtained even intermittently, the measured distance value R during this period is as shown in FIG.
It goes without saying that a safe result can be obtained by replacing the corrected distance value R (N) with the average value obtained by sliding the average of several times in (i) and displaying it.

[Measurement Principle] The reason why the corrected distance value Rc at the present time can be obtained by the above arithmetic expression, that is, the principle of the measurement method will be described below. In FIG. 12, at a certain measurement point, the relationship between the true initial measured distance value R _T (0) and the true displacement amount r _T (i) with respect to the true distance value R _T (i) can be expressed by the following equation. .

[Equation 6]

The error value of each measured distance value R (i) is ε _R (i), and the error value of each measured displacement amount r (i) is ε.
_{Assuming r} (i), as described above, the error value in the case of Doppler displacement measurement, that is, ε _r (i), becomes the error value in the case of pulse reflection type distance measurement, that is, ε _R (i). By comparison, it is much smaller, so we can relate it as follows:

[Equation 7]

The error value of the initial measured distance value R (0) is set to ε _R
(0) and the measurement error value for each time is ε (i),

[Equation 8]

Therefore, the estimated value R (0) of R (0) is minimized so that the sum of squares of the error value ε (i) is minimized from the measured values of the measured displacement amount r (i) and the measured distance value R (i). R (0,
i) ", the estimated value" R of the measured distance value R (i) "
Since (i) ”should be set to the corrected distance value Rc, it can be set as in the following equation.

[Equation 9]

Although no coefficient is provided for r (i) in the equation (13), the coefficient α is provided for the sake of convenience in the calculation process of the estimation calculation, and N measurements are made up to the present time. Assuming that the distance value R (i) and the measured displacement amount r (i) are obtained, the following equation is obtained from the equation (10).

[Equation 10]

Here, in order to make the above expression (14) into a matrix expression, if the symbol * indicating the vector and the matrix Z are set,

[Equation 11]

From these equations, the above equation (14) is obtained.
Can be expressed simply as

[Equation 12]

Here, since the quantity to be estimated is the vector * θ including α and R (0), here, the variance matrix of the estimation error is set to P (i) by using the least square method. When the weight is set to ρ, the least squares estimated value “* θ (N)” can be expressed as the following equation.

[Equation 13]

Since the load ρ is a value close to 1 sufficiently,
As an initial value,

[Equation 14]

Furthermore, C, P ₁₁ , P ₁₂ , P ₂₁ , P ₂₂ , and P ₂₂ , as an intervening symbol for contributing to the expansion of the equation.
When q, s, t, u, and v are set, the coefficient estimated value “α (N)” and the estimated distance value “R (0, N)” are
It can be expressed by the following equation.

[Equation 15]

Then, in these equations,

[Equation 16] Further, the value obtained by calculating “R (0, N)” by the equation (26) is used as the estimated value “R (0, N)” of the equation (13).
i) ”, the corrected distance value Rc to be obtained can be obtained.

That is, "α (N)" in the equation (25) is "α
(I) ”,“ R (0, N) ”in the equation (26) is“ R
(0, i) ”, and r (N) in equations (25) and (26) can be written as r (i), so that equation (1
3) can be solved.

To summarize the configuration according to the first embodiment described above, as the first configuration, a periodically repeated transmission wave, for example, a reflected wave of the transmission pulse wave A, for example, the transmission pulse wave B is used.
And the measured distance value obtained based on the measured value of the amount of time from the specified point a of each cycle of the transmitted wave to the specified point b corresponding to the specified point a of the reflected wave is the frequency fo of the transmitted wave.
In the distance measuring method for obtaining the corrected distance value by correcting the measured displacement amount obtained based on the measured value of the frequency change amount or the phase change amount of the reflected wave, the optimum estimation calculation for performing the correction is sequentially performed. The present invention provides a distance measuring method adapted to perform a calculation by using convergence by a type least square method.

As a second structure, in the distance measuring method according to the first structure, the initial measured distance value obtained at a predetermined time point is R (0), and each time measurement is made after the predetermined time point. The displacement amount is r (i), and the measured distance value for each measurement is R
(I) In addition, the corrected distance value is Rc, and the estimated value of the measured distance value that minimizes the sum of squared errors is “R (0, i)”,
The present invention provides a distance measuring method for performing a calculation to obtain a corrected distance value by a calculation formula Rc = “R (i)” = “R (0, i)” + r (i).

As a third structure, in a device using the distance measuring method according to the first structure or the second structure, the distance measuring unit for measuring the amount of time for obtaining the measured distance value. For example, the distance measuring unit 1 and a displacement measuring unit that measures the amount of frequency change or the amount of phase change for obtaining the amount of measurement displacement, for example, the displacement measuring unit 2, the amount of time, and the frequency change described above. A correction distance value calculator for obtaining the above-mentioned correction distance value by measuring the above-mentioned measured distance value and the above-mentioned change amount based on the amount or the phase change amount, and performing the calculation based on the above-mentioned arithmetic expression, for example, The present invention provides a distance measuring device provided with a corrected distance value calculation unit 3.

[Second Embodiment] Next, referring to FIGS.
A second embodiment will be described. 1 to 4 in FIGS.
The parts denoted by the same reference numerals as in FIG. 4 have the same functions as the parts denoted by the same reference numerals explained in FIGS. 1 to 4, and the signals of the respective parts in the configuration of FIG. 5 are shown in FIGS. .

In FIG. 5, an oscillating circuit 11 generates an oscillating signal 11a which is a rectangular wave or a narrow pulse wave by differentiating or hard limiting a signal obtained by oscillating a continuous wave having a frequency higher than the frequency to be transmitted. Then, it is applied to the first frequency dividing circuit 12 and the 90 ° / 2-phase circuit 22.

The first frequency dividing circuit 12 divides the frequency of the oscillation signal 11a to obtain the frequency f0 of the transmission wave C as described with reference to FIG.
The first frequency-divided signal 12a having a rectangular wave having a period t0 corresponding to the signal of
And the two-phase circuit 22.

The second frequency dividing circuit 13 has a first frequency dividing signal 12a.
Is further divided into a cycle T and a pulse width t1 for repeatedly transmitting a pulse p1 having a pulse width t1 in FIG. 6 corresponding to the transmission pulse wave A as described in FIG. 10 at a predetermined cycle. And a pulse width t1 is selected for each cycle T to generate a transmission pulse wave signal 13a, which is applied to the modulation circuit 14 and the comparison circuit 26.

The modulation circuit 14 modulates the first divided signal 12a with the transmission pulse wave signal 13a. In this case,
The modulated wave signal 14a is generated by modulating at an intermediate modulation rate, for example, a modulation rate of about 50%, and is provided to the transmission circuit 15.

The transmitting circuit 15 power-amplifies the modulated wave signal 14a and supplies the amplified wave signal 14a to the wave transmitter 16 so that the signal shown in FIGS.
A signal obtained by combining the transmission pulse wave A and the transmission wave C described in 3 is transmitted as the transmission wave A1 toward the target E. Also,
If necessary, a resonance circuit having a frequency corresponding to the cycle t0 may be interposed.

The received signal obtained by receiving the reflected wave B1 from the target E by the wave receiver 17 is amplified by the amplifier circuit 18 to a desired amplitude value, and the reception described with reference to FIGS. Pulse wave B
A reception signal 18a is generated by combining the received signal D and the received wave D, and the reception signal 18a is given to the amplitude limiting circuit 20 and the detection circuit 25.

The detection circuit 25 amplitude-detects the reception signal 18a having a waveform similar to that of the reflected wave B1 to produce the reception pulse wave signal 25a having a waveform corresponding to the reception pulse wave B described in FIG. The waveform is shaped accordingly and then provided to the comparison circuit 26.

The comparison circuit 26 detects the time ta corresponding to the period from the defined point a to the defined point b described with reference to FIG. 10, and it includes the transmission pulse wave signal 13a and the reception pulse wave signal 2
5a, for example, the transmission pulse wave signal 13a is the rising point of the transmission pulse p1, the reception pulse wave signal 25a is the intermediate amplitude point of the rising of the reception pulse p2,
Alternatively, by each signal obtained by detecting a predetermined amplitude point of the waveform obtained by differentiating the rising portion of the reception pulse p2,
A gate signal that gates the period of each signal is given to the gate circuit 19 as the comparison detection signal 26a.

The gate circuit 27 uses a clock pulse (not shown), for example, a pulse obtained by gating the oscillation signal 11a of the oscillation circuit 11 with the comparison detection signal 26a, that is, the time ta described in FIG. 10, that is, the distance to the target E. The pulse amount corresponding to the time amount corresponding to the value or the voltage amount obtained by integrating the period of the comparison detection signal is given to the A / D conversion circuit 31 as the time amount signal 27a.

The A / D conversion circuit 31 is a circuit group having a plurality of A / D conversion circuits, and converts the time amount signal 26a into a digital value signal and gives it to the CPU 32. The amplitude limiting circuit 20 gives a signal whose amplitude has been limited so that the amplitude of the received signal 18a is constant, to the filtering circuit 21. Filtering circuit 21
Is a band-pass type filtering circuit, and is a carrier wave in the received signal 18a, that is, a sinusoidal signal in which the frequency component corresponding to the period t0 of the first divided signal 12a is phase-shifted or frequency-shifted, That is, the frequency fs of the received wave D in FIG.
Received phase signal 2 obtained by filtering and extracting
1a is supplied to the sample hold circuit 23 and the sample hold circuit 24.

Since the target E is phase-shifted by the movement of the target E, the reception phase signal 21a is, for example, a signal of the phase φ1 or a signal of the phase φ2 shown in FIG. When the signal has a delayed phase as described above and the moving speed is higher, it appears as a frequency shift in which the phase shift is accumulated.

The 90 ° / 2-phase circuit 22 uses the first divided signal 1
A two-phase frequency signal having a phase difference of 90 ° from 2a is obtained. The sampling time point signal 22a, that is, 90 degrees, is used to sample the time point of a phase obtained by shifting the period t0 of the first divided signal 12a by ¼ ° Phase-shifted signal and first divided signal 1
2a is a circuit for obtaining a two-phase signal with a sample time point signal 22b for sampling the time point of the phase of itself, and the sample time point signal 22a is sent to the sample hold circuit 23, and the sample time point signal 22b is sent to the sample hold circuit 2
Give to 4.

The 90 ° / 2-phase circuit 22 is, for example,
A combination of a one-shot multivibrator and a counter is used, and a pulse having a narrow width corresponding to the rising edge of the first divided signal is generated by the one-shot multivibrator to obtain the sample time point signal 22a, and the first divided signal 12
It is possible to set the frequency division ratio of a to 4 and generate a narrow pulse after one pulse of the first frequency division signal 12a from the rising edge of the first frequency division signal to obtain the sampling time point signal 22b. I can. The frequency division ratio is set to an integral multiple of 4, and 1/4 of the reciprocal of the frequency division ratio is calculated from the rising edge of the first frequency division signal.
It is also possible to obtain the sampling time point signal 22b by making a pulse having a narrow width at the time point when the pulses of the transmission signal 11a are counted by the number corresponding to.

The sample-and-hold circuits 23 and 24 hold the signal of the level value obtained by sampling the reception phase signal 21a and update and hold the sampled level value for each new sample. The sample-hold signal 23a and the sample-hold signal 24a obtained by sample-holding are applied to the A / D conversion circuit 31.

In FIG. 8, the signal shown by the solid line of the reception phase signal 21a shows the case of the detection reference phase, that is, the detection phase of 0 °, and the signal shown by the broken line is the signal shifted by only phase φ1 and phase φ2. Shown, the sample time point signal 22a
When the detection reference phase is used as a reference, the phases of the sampling time point signal 22b and the sampling time point signal 22b correspond to a phase point for obtaining the sin component level and a phase point for obtaining the cos component level, respectively. The 90 ° / 2-phase circuit 22 and the sample hold circuits 23 and 24 are
A sample hold signal 23a and a sample hold signal 24a are obtained as signals obtained by multiplying the signal of the sin component and the signal of the cos component by the independent / 2 phases by the reception phase signal 21a.

Therefore, as shown in FIG. 9, when the detection reference phase is set right above 0 and the polar angle is taken in the clockwise direction, the sample hold signal 23a and the sample hold signal 24a have the respective levels. The polarities are arranged as shown in FIG. 9, and the angle value between the phase φ1 and the phase φ2 is detected by the polar coordinate value.

In the A / D conversion circuit 31, each level value of the sample and hold signals 23a and 24a is converted into a digital value and given to the CPU 32.

The CPU 32 has a digital value corresponding to a distance value from the A / D conversion circuit 31 to the target E and a displacement amount of the target E, that is, a digital value based on the gate count signal 27a, and a sample hold. Signals 23a and 24a
Based on these digital values and the required coefficient values stored in advance in the CPU 32, the measured distance value R is stored.
(I) and the measured displacement amount r (i) are measured, and based on these measured values, the optimum estimation is applied by applying the convergence calculation by the recursive least squares method described in the first embodiment. Then, a process for obtaining a target corrected distance value R (N) is performed, and the obtained corrected distance value R (N) is stored and held.

Corrected distance value R stored in the CPU 32 every time
2 to 4 are displayed on the display 43 based on the analog value data obtained by D / A converting the data obtained by reading the data obtained by reading (N) with the printer 41. It is for displaying a figure.

To summarize the second embodiment described above, as the fourth configuration, in the distance measuring method according to the first configuration or the second configuration described in the first embodiment, the modulated wave signal 14a shown in FIG. 6 is used. As described above, with one continuous wave, for example, a transmission wave, for example, a pulse p1 in which the amplitude of a waveform such as the first frequency-divided signal 12a is partly pulse-modulated at a required period, for example, a period T1. Distance measurement using a modulated transmission wave, using the above-mentioned pulse-shaped portion as the transmission wave for obtaining the above measurement distance value, and using the above continuous wave as the transmission wave for obtaining the above measurement displacement amount It provides a method.

As a fifth configuration, in the distance measuring method according to the fourth configuration, the distance measurement is performed by using a transmission wave which is obtained by modulating the amplitude modulation with an intermediate modulation rate, for example, 50% modulation. It provides a method.

A sixth structure is a distance measuring device using the distance measuring method according to the first structure, the second structure, the fourth structure, and the fifth structure described above, wherein Transmitting circuit for transmitting, for example, oscillating circuit 11 / first
A circuit composed of the frequency dividing circuit 12, the second frequency dividing circuit 13, the modulating circuit 14, the transmitting circuit 15 and the like, a receiving circuit for receiving the reflected wave of the transmitting wave, an amplifying circuit 18, an amplitude limiting circuit 20, and a detecting circuit. 25, a reference wave circuit that obtains a sine wave signal and a cosine wave signal having the frequency of the transmission wave, for example, a circuit that is configured by a 90 ° / 2-phase circuit 22 and the like, and the above reception circuit By detecting the frequency signal of the reflected wave obtained by the above method based on the sine wave signal and the cosine wave signal, for example, the sample hold circuit 2
3. The amount of time between the displacement amount measuring means for obtaining the above-mentioned measured displacement amount and the pulse signal of the reflected wave and the pulse signal of the transmitted wave, which are obtained by the receiving circuit, by the circuit configured by the sample hold circuit 24 and the like. On the basis of the above, for example, by the circuit configured by the comparison circuit 26 and the gate circuit 27, the distance value measuring means for obtaining the above measured distance value, and the above calculation based on the above measured displacement amount and measured distance value. The present invention provides a distance measuring device provided with an optimum estimation calculation means for obtaining a corrected distance value by performing a calculation by an expression by the CPU 32, for example.

As a seventh configuration, in the distance measuring device according to the sixth configuration, the displacement amount measuring means, the distance value measuring means, and the optimum estimation calculating means are combined into one C.
The present invention provides a distance measuring device provided with a calculation unit that is calculated by a PU, for example, a CPU 32.

[Modified Implementation] The present invention can be modified and implemented as follows. (1) A pulse wave for distance measurement is transmitted by the output that detects that the reflected wave used for measuring the displacement amount cannot be obtained,
Alternatively, it is configured to perform pulse modulation for distance measurement.

(2) The display unit 43 is constructed by providing a distance value display by digital value and a distance value display by analog value, and the distance value display by analog value is provided.

(3) The analog display of (2) above is converted into analog signals of the sample and hold signals 23a and 24a, or analog signals corresponding to these signals obtained from the D / A converter 42, as shown in FIG. As described above, by giving the X and Y deflection electrodes of the cathode ray tube with the required polarities, the phase point image corresponding to the phase φ1, the phase φ2, etc. is displayed, and the distance value is small by the unit distance scale provided in the periphery. Make it possible to read the change situation in a fine analog manner. Further, the displayed analog value signal is formed into a sawtooth wave so that a phase line image is displayed for easy viewing. Further, instead of the cathode ray tube, a two-phase meter is used for the display.

(4) The 90 ° / 2-phase circuit 22 and the sample-hold circuits 23 and 24 are used to obtain the multiplication calculation force, and the output of the 90 ° / 2-phase circuit is represented by a sine wave waveform.
By changing the in-component signal and the cos-component signal to the sample-hold circuits 23 and 24 and the multiplying circuit, and applying the output of the multiplying circuit to the integrating circuit, the filtering circuit, or a combination thereof, It is configured to obtain a similar multiplication calculation force.

(5) In a configuration such as an α-β-γ tracker for tracking a distance and a direction, the distance measuring method or the distance measuring in each of the above-mentioned embodiments and each modified embodiment is performed in the portion for tracking the distance. Configured using the device.

(6) A variation amount Δf of the frequency obtained by comparing the reception frequency fs with the transmission frequency f0 in the analog measurement portion for obtaining the measurement displacement amount r (i) of the first or second embodiment. The phase change amount Δp is detected, and the corresponding shift amount is obtained from Δf or Δp.

(7) The modulation of the transmission wave A1 by the pulse p1 in the second embodiment is full amplitude modulation, that is, 100% modulation, and the pulse width t1 of the pulse p1 is set by the sample hold signals 23a and 24a. Change the configuration so that the time is long enough to achieve the purpose.
Further, in the case of this configuration, the short wave t1 in the transmission wave A1 of FIG. 7 is formed so as to have no amplitude,
The received pulse wave signal 25a shown in FIG. 7 is configured to have a reverse waveform to detect the time ta, or the received signal 18a is reversely detected to obtain the same waveform as the received pulse wave signal 25a shown in FIG. . In this configuration, in the distance measuring method as in the first configuration and the second configuration described above, a transmission wave in which the total amplitude of one carrier is amplitude-modulated with a pulse having a required period is used, and a part of this pulse is used. To configure a distance measuring method that uses a transmission wave for obtaining the above-mentioned measured distance value and uses a carrier wave included in this pulse as a transmission wave for obtaining the above-mentioned measurement displacement amount. Become.

(8) The transmission wave transmitted from the distance measuring unit 1 is sequentially divided into a plurality of intervals of the repetition cycle T,
Alternatively, the measured distance is obtained by changing the frequency in a predetermined order to obtain a frequency-modulated waveform, and the distance measuring unit 1 detects a frequency change point of the frequency-modulated waveform as a specified point for distance measurement. To get the value,
Further, the shift measuring unit 2 is configured to obtain the measurement shift amount by detecting the amount of frequency change or the amount of phase change in the received signal for a predetermined frequency whose frequency is changing or each frequency.

(9) In the configuration of the second embodiment or the above (8), a signal of a frequency obtained by frequency-converting the frequency of the received signal of the reflected wave, for example, an intermediate frequency signal by the superheterodyne amplifier circuit is received. The signal 18a is obtained, and the frequency signal for detecting the frequency change amount or the phase change amount in the received signal or the signal having the cycle for obtaining the 90 ° / 2-phase signal is frequency-converted from the frequency of the transmitted wave. It is configured to be obtained from the signal obtained by the above or a signal of the frequency of an independent oscillator.

(10) Instead of the first frequency dividing circuit 12, the second frequency dividing circuit 13, and the 90 ° / 2-phase circuit 22 which control the period of the transmitted wave, the frequency dividing portion by these is controlled by the CPU.
The counting process by 32 is performed. Further, in this case, the clock signal of the CPU 32 is used instead of the oscillation signal 11a of the oscillation circuit 11 as necessary. According to this configuration, in the distance measuring device as in the seventh configuration, the control of the cycle of the transmission wave, the displacement amount measuring means, the distance value measuring means, and the optimum estimation calculating means are combined into one unit. This constitutes a distance measuring device provided with a computing means for computing by the CPU.

(11) The calculation part for obtaining the measured distance value, the calculation part for obtaining the measurement displacement amount, and the calculation part for performing the optimum estimation calculation process are configured to perform calculation using separate CPUs.

(12) The transmission wave for obtaining the measurement distance value and the transmission wave for obtaining the measurement displacement amount are performed by separate transmission waves, and the circuit portion and the measurement deviation for obtaining the measurement distance value are used. The circuit portion for obtaining the quantity is configured as an independent separate circuit.

[0080]

According to the present invention, as described above, the pulse reflection type distance measurement and the Doppler displacement amount measurement are engaged, and the convergence calculation by the recursive least squares method is performed for the optimum estimation. Since an extremely long calculation for solving a complicated equation is not required, it is possible to use an online configuration even when the speed of the moving body changes rapidly or when you want to obtain detailed movement data. There is a feature of.

[Brief description of drawings]

1 to 9 show an embodiment of the present invention, and FIG.
0 to 13 show the prior art, and the contents of each figure are as follows.

FIG. 1 is a block diagram

[Fig. 2] Plot diagram of measurement results

[Fig. 3] Plot diagram of measurement results

[Fig. 4] Plot diagram of measurement results

FIG. 5 is a circuit block configuration diagram.

FIG. 6 is a signal waveform diagram of essential parts.

FIG. 7 is a signal waveform diagram of essential parts.

FIG. 8 is a signal waveform diagram of essential parts.

FIG. 9: Polar coordinate display diagram of phase change

FIG. 10 is a signal waveform diagram of essential parts.

FIG. 11 is a signal waveform diagram of essential parts.

FIG. 12: Plot diagram of measurement results

FIG. 13 is a signal waveform diagram of essential parts.

[Explanation of symbols]

 1 distance measuring unit 2 displacement measuring unit 3 corrected distance value calculating unit 4 display unit 11 oscillation circuit 11a oscillation signal 12 first frequency dividing circuit 12a first frequency dividing signal 13 second frequency dividing circuit 13a second frequency dividing signal 14 modulation circuit 14a Modulated wave signal 15 Transmitter circuit 16 Transmitter 17 Receiver 18 Amplifier circuit 18a Received signal 20 Amplitude limiting circuit 21 Filtering circuit 21a Received phase signal 22 90 ° / 2-phase circuit 22a Sample time point signal 22b Sample time point signal 23 Sample hold Circuit 23a Sample and hold signal / sin component signal 24 Sample and hold circuit 24a Sample and hold signal / cos component signal 25 Detection circuit 25a Received pulse wave signal 26 Comparison circuit 26a Comparison detection signal 27 Gate circuit 27a Time amount signal 31 A / D conversion circuit 32 CPU 41 Printer 42 D / A Circuit 43 display A transmitted pulse wave A1 transmission wave B receiving pulse wave B1 reflected wave C transmission wave D received wave T period t0 period t1 pulse width p1 pulse p2 pulse

Claims (10)

[Claims] 1. A reflected wave of a periodically repeated transmission wave is obtained, and based on a measured value of a time amount from a specified point of each cycle of the transmitted wave to a specified point corresponding to the specified point of the reflected wave. A distance measuring method for obtaining a corrected distance value by correcting the obtained measured distance value with a measured displacement amount obtained based on the measured value of the frequency change amount or the phase change amount of the reflected wave with respect to the frequency of the transmitted wave, A distance measuring method, characterized in that the calculation of the optimum estimation for performing the correction is performed by using the convergence by the recursive least squares method. 2. The distance measuring method according to claim 1, wherein an initial measured distance value obtained at a predetermined time point is R (0), and a measurement displacement amount obtained every time after the predetermined time point is r (i). ,
R (i) is the measured distance value for each time, and R is the corrected distance value.
c, the estimated value of the measured distance value that minimizes the sum of squared error is “R (0, i)”, and the arithmetic expression Rc = “R (i)” = “R (0, i)” + r (i) A distance measuring method, characterized in that a calculation for obtaining a corrected distance value is performed. 3. The distance measuring method according to claim 1, wherein the amplitude of one continuous wave is partly pulse-modulated at a required period to form a pulse wave, and the pulse wave part is used. Is used as a transmission wave for obtaining the measurement distance value, and the continuous wave is used as a transmission wave for obtaining the measurement displacement amount. 4. The distance measuring method according to claim 3, wherein a transmission wave obtained by modulating the amplitude modulation with an intermediate modulation rate is used. 5. The distance measuring method according to claim 1 or 2, wherein a transmission wave in which the total amplitude of one carrier is amplitude-modulated with a pulse having a required period is used, and a portion of the pulse is used as the measured distance. A distance measuring method, wherein a transmission wave for obtaining a value is used, and the carrier wave included in the pulse is used as a transmission wave for obtaining the measurement displacement amount. 6. A distance measuring device using the distance measuring method according to claim 1 or 2, wherein a distance measuring section for measuring an amount of time for obtaining the measured distance value, and for obtaining the measured displacement amount. Of the displacement measurement unit that measures the amount of frequency change or the amount of phase change, the amount of time, and the measurement distance value and the amount of change based on the amount of frequency change or the amount of phase change, the arithmetic expression A distance measuring device, comprising: a corrected distance value calculation unit that performs a calculation based on the corrected distance value calculation unit. 7. A distance measuring device using the distance measuring method according to claim 3, 4, or 5, wherein a distance measuring unit for measuring an amount of time for obtaining the measured distance value; A displacement measuring unit that measures the amount of frequency change or the amount of phase change to obtain the amount, while measuring the time distance and the measured distance value and the amount of change based on the amount of frequency change or the amount of phase change. A distance measuring device for calculating a corrected distance value by performing a calculation based on the calculation formula. 8. The distance measuring device according to claim 6, wherein the transmitting circuit transmits the transmitting wave, the receiving circuit receives the reflected wave of the transmitting wave, and the frequency of the transmitting wave. A reference wave circuit for obtaining a sine wave signal and a cosine wave signal having a frequency signal of a reflected wave obtained by the receiving circuit, based on the sine wave signal and the cosine wave signal, the measurement A displacement amount measuring unit for obtaining a displacement amount, a distance value measuring unit for obtaining the measured distance value based on the amount of time between the pulse signal of the reflected wave and the pulse signal of the transmitted wave obtained by the receiving circuit, A distance measuring device comprising: an optimum estimation calculation means for obtaining the corrected distance value by performing a calculation by the calculation formula based on the measured displacement amount and the measured distance value. 9. The distance measuring device according to claim 8, further comprising arithmetic means for arithmetically operating the displacement amount measuring means, the distance value measuring means, and the optimum estimation arithmetic means by one CPU. A characteristic distance measuring device. 10. The distance measuring device according to claim 8, wherein the control of the cycle of the transmitted wave, the displacement amount measuring means, the distance value measuring means, and the optimum estimation calculating means are performed by one CPU. A distance measuring device comprising a calculating means for calculating.