JP2007192575A - Target positioning device - Google Patents

Abstract

[PROBLEMS] To provide a low-speed signal processing and high resolution in a narrow receiver band, which does not require time synchronization between a transmitting station and a receiving station, and is composed of a small receiving station having a small-diameter antenna, and is flexible in operation. And provide a low-cost target positioning device.
The target positioning device includes a transmitting station that radiates FMCW radio waves, and three or more receiving stations that mix a direct wave or a target reflected wave with a local signal similar to the FMCW radio wave to generate a direct beat signal or target. Obtain the reflected beat signal, calculate the direct wave frequency that maximizes the output of the direct beat signal, calculate the target reflected wave frequency that maximizes the output of the target reflected beat signal, and calculate the calculated direct wave frequency and the target reflected wave Based on the frequency, the distance sum and the relative speed sum between the transmitting station and the receiving station are estimated, and the target position / speed estimator calculates the target 3D position coordinates and 3D relative speed from the distance sum and the relative speed sum. Estimate the components.
[Selection] Figure 1

Description

  The present invention relates to a target positioning device that is installed at a point where a transmission antenna and a reception antenna are different and measures the position of a target object.

Bistatic radars install a transmitting antenna and a receiving antenna at different points, and measure the position of a target object. Since the time between the transmitting station and the receiving station must be synchronized in order to measure the distance to the target object, a transmission pulse that transmits a pulse for time synchronization using a Loran (Long Range Navigation) radio wave is used. A method of generating and transmitting / receiving transmission pulse information indicating the period, time, and phase is employed (see, for example, Patent Document 1 and Patent Document 2).
In addition, time synchronization between the transmitting station and the receiving station is not performed, and there are a plurality of receiving stations. Specify (for example, refer to Patent Document 3).

JP-A-7-140124 JP 2003-156557 A JP-A-6-148318

However, in order to synchronize the time between the transmitting station and the receiving station, a synchronization pulser and transmission pulse information are required, and in order to obtain high distance accuracy, a wideband receiving system and high-speed signal processing are required. . In addition, there is a problem that a large-scale expensive antenna with a large aperture diameter is required to measure the angle with high accuracy in the receiving system.
In addition, in order to obtain the time difference between the direct wave pulse and the target reflected pulse with high accuracy at the receiving station, there is a problem that high-speed correlation processing with a broadband receiver is necessary and the device scale becomes large. In addition, there is a problem that it is impossible to measure the relative speed with high accuracy using the Doppler frequency.

  The object of the present invention is a small receiver station having a low-speed signal processing and high resolution in a narrow receiver band, no need for time synchronization between the transmitter station and the receiver station, and a small-diameter antenna, It is to provide a target positioning device that is flexible in operation and low in cost.

  The target positioning apparatus according to the present invention includes a transmitting station that radiates radio waves, three or more receiving stations that receive radio waves that arrive directly or after being reflected by a target object, and a target position and velocity based on the received radio waves. In the target positioning device including a target position / speed estimator for estimating the transmission FMCW signal generator, a transmission FMCW signal generator for generating a transmission FMCW signal, a transmission signal converter for modulating radio waves with the transmission FMCW signal, And the receiving station mixes the received FMCW signal generator for generating a local signal having the same sweep slope and sweep time as the FMCW signal, the radio wave received from the transmitting station and the local signal, and beats the received FMCW signal generator. A reception signal converter for obtaining a signal, a beat frequency at which the output of the beat signal is maximized, a frequency analysis means for calculating a time error, and the beat signal Distance sum speed sum estimating means for estimating a sum of distances and a relative speed sum between the transmitting station and the receiving station based on a wave number and the time error, and the target position / speed estimator includes the receiving position The target three-dimensional position coordinate is estimated based on the distance sum input from the station and the time error, and the target three-dimensional relative speed component is calculated based on the three-dimensional position coordinate and the relative speed sum. presume.

  The effect of the target positioning apparatus according to the present invention is that the radio wave modulated by the FMCW signal is used, it is not necessary to synchronize the time of the receiving station with the time of the transmitting station, and no synchronization pulser or transmission pulse information is required. Even with a band receiving system and low-speed signal processing, high-accuracy position resolution can be realized, and the receiving station can be made small and movable, thereby ensuring operational flexibility. In addition, since the radio wave modulated by the FMCW signal is used, the relative velocity can be measured with high accuracy using the Doppler phenomenon.

Embodiment 1 FIG.
FIG. 1 is a configuration diagram of a target positioning apparatus according to Embodiment 1 of the present invention. FIG. 2 is a diagram illustrating the positions of the transmitting station, the receiving station, and the target on the XY coordinate plane. FIG. 3 is a diagram illustrating a change in frequency of the FMCW signal at the transmitting station and the receiving station.
A target positioning apparatus 1 according to Embodiment 1 of the present invention includes one transmitting station 2, three receiving stations 3a, 3b, 3c and a target position / speed estimator 4 as shown in FIG. The sum of distances and the sum of relative velocities obtained in each of the receiving stations 3a to 3c are sent to the target position / speed estimator 4 using a general communication means. The target positioning device 1 according to the first embodiment includes three receiving stations 3, but may include four or more receiving stations 3.

The transmitting station 2, the receiving stations 3a to 3c and the target 20 are arranged as shown in FIG. When the coordinates of the transmitting station 2 are placed at the origin of the XYZ coordinate system, the position vectors of the receiving stations 3a to 3c are _Xn . n is a number for identifying the receiving stations 3a to 3c. Since three receiving stations 3a to 3c are provided, n = 1, 2, and 3. This position vector _Xn is known. The position vector X of the target 20 is an unknown value obtained by the target positioning device 1.
In FIG. 2, R ₀ is the distance between the transmitting station 2 and the target 20, R _n is the distance between the target 20 and the receiving station 3 with the identification number n, and R _0n is the receiving position with the transmitting station 2 and the identification number n. This is the distance between stations 3.
V ₀ is the relative speed between the transmitting station 2 and the target 20, v _n is the relative speed between the target 20 and the receiving station 3 with the identification number n, and v _0n is the receiving station with the transmitting station 2 and the identification number n. 3 relative speed.

As shown in FIG. 1, the transmitting station 2 transmits a transmission frequency modulated continuous wave signal (hereinafter abbreviated as FMCW signal), a transmission FMCW signal generator 5 and a transmission FMCW input from the transmission FMCW signal generator 5. A transmission signal converter 6 that modulates radio waves according to a signal and a transmission antenna 7 that radiates radio waves into the air are provided.
The transmission FMCW signal generator 5 generates a transmission FMCW signal that specifies the frequency of the frequency modulation processing performed in the transmission signal converter 6. Transmitting FMCW signal, as shown in FIG. 3 (a), the center frequency f, the sweep bandwidth B, and the sweep time _{T C,} for each sweep gradient sweep time _{T C μ1} = B / _{T C} and _mu 2 = switches to and -B / _{T C.}

The transmission signal converter 6 modulates the signal into a continuous wave having a frequency specified by the transmission FMCW signal and outputs the modulated signal to the transmission antenna 7. The radio Tx _i emitted is represented by the formula (1). i is a number identifying the sweep slope μ ₁ or the sweep slope μ ₂ and is 1 or 2. In order to facilitate understanding of the explanation, the envelope 1 has a constant amplitude.

  As shown in FIG. 1, each of the receiving stations 3 a to 3 c receives a reception antenna 8 that receives radio waves that propagate through the air and a reception FMCW signal generator 9 that generates a local signal based on the reception FMCW signal. A local signal is mixed with radio waves, a sum signal of frequencies is removed by a low-pass filter, a received signal converter 10 for generating a beat signal, and an FMCW signal processor for processing a beat signal to estimate a distance sum and a relative velocity sum 11 is provided.

The radio wave radiated from the transmitting antenna 7 into the air reaches the receiving antenna 8 directly or after being reflected by the object of the target 20. In the following description, radio waves that arrive after being reflected by the object of the target 20 are referred to as target reflected waves, and radio waves that arrive directly are referred to as direct waves.
The target reflected wave Rx _{1, n} is expressed by Expression (2). τ ₀ is the propagation time of the radio wave between the transmission station 2 and the target 20 at time t = 0, and is expressed by Expression (3) when the distance R ₀ between the transmission station 2 and the target 20 is used. τ _n is the propagation time of the radio wave between the target 20 and the receiving station 3 with the identification number n at the time t = 0, and using the distance R _n between the target 20 and the receiving station 3 with the identification number n, the equation (4 ). v ₀ is the relative speed between the transmitting station 2 and the target 20 at time t = 0, and v _n is the relative speed between the target 20 and the receiving station 3 with the identification number n at time t = 0. c is the speed of light.

Further, the direct wave Rx0 _{i, n} is expressed by Expression (5). Note that the direct wave is distinguished from the target reflected wave by time division and measuring when there is no target 20, or by measuring a gain difference due to antenna beam scanning. Even when the observation is performed simultaneously, the target reflected wave and the direct wave can be separated by making the relative speed between the transmitting station 2 and the receiving station 3 known to some extent (for example, both are stationary). In the following description, it is assumed that they are received separately.

The reception FMCW signal generator 9 generates a reception FMCW signal that generates a local signal for mixing the received radio wave in the reception signal converter 10, generates a local signal using the reception FMCW signal, and converts the reception signal. To the device 10. Received FMCW signal, as shown in FIG. 3 (b), transmitted FMCW signal as well as the center frequency f, the sweep bandwidth B, and the sweep time _{T C,} for each sweep gradient sweep time _{T C μ1} = B / T _C and _μ 2 = switched on and -B / _{T C.} However, there is a time difference δt _n between the transmitting station 2 and the receiving station 3.
The local signal L _{i, n} generated by the reception FMCW signal generator 9 is expressed by Expression (6).

The reception signal converter 10 mixes the target reflected wave Rx _{i, n} with the local signal L _{i, n} , passes through the low-pass filter, removes the frequency sum signal, and obtains the target reflected beat signal B _{i, n.} . The target reflection beat signal B _{i, n} is expressed by Expression (7). Incidentally, the speed _v 0, _{v n} than the velocity of light c is assumed to be sufficiently small.
Further, the direct wave Rx0 _{i, n} is mixed with the local signal L _{i, n} , passes through the low-pass filter, the frequency sum signal is removed, and the direct beat signal B0 _{i, n} is obtained. The direct beat signal B0 _{i, n} is expressed by equation (8).

As shown in FIG. 1, the FMCW signal processor 11 includes a target reflected wave frequency analysis unit 14, a direct wave frequency analysis unit 15, a time error estimation unit 16, and a distance sum speed sum estimation unit 17 as the frequency analysis unit 13. Have.
The target reflected wave frequency analyzing means 14 performs a Fourier transform on the target reflected beat signal B _{i, n} and obtains a target reflected beat frequency f _{i, n} (bar) at which the output reaches a peak from the equation (9).

The direct wave frequency analyzing means 15 performs a Fourier transform on the direct beat signal B0 _{i, n} and obtains a direct beat frequency f0 _{i, n} (bar) at which the output reaches a peak from the equation (10).

The time error estimating means 16 uses the detected target reflection beat frequency f _{i, n} (bar) and the direct beat frequency f0 _{i, n} (bar) to calculate the transmitting station 2 and the receiving stations 3a to 3 from the equation (11). A time error δt _n (hat) between 3b is obtained.

The distance sum speed sum estimating means 17 uses the time error δt _n (hat) between the transmitting station 2 and the receiving stations 3a to 3b, from the equation (12), the transmitting station 2, the target 20, the target 20, and each reception. A sum ξ _n (hat) between the stations 3a to 3c is obtained.
In Expression (12), the frequencies μ ₁ and μ ₂ are set values, and the target reflection beat frequency f _{1, n} (bar), the target reflection beat frequency f _{2, n} (bar), and the time error δt _n (hat) are It is obtained by Fourier transform. Since the distance R _0n between the transmitting station 2 and each receiving station 3 is known, the time delay τ _0n is known, and the distance sum ξ _n (hat) is obtained from the equation (12).

Further, the distance sum speed sum estimating means 17 uses the time error δt _n (hat), the distance sum ξ _n (hat) and the target reflection beat frequency f _{1, n} (bar), at each of the receiving stations 3a to 3c. The relative speed sum V _n (hat) between the transmitting station 2 and the target 20 and between the target 20 and each of the receiving stations 3a to 3c is obtained from the equation (13).

The target position / speed estimator 4 estimates the three-dimensional coordinates and the three-dimensional relative speed component of the target 20 according to the following procedure.
Since the position vector of the known transmitting station 2, the position vector of each known receiving station 3, and the position vector of the unknown target 20 to be estimated are X ₀ , X _n , and X, respectively, the distance sum of Expression (12) By using ξ _n , the relational expression of Expression (14) is established.
Then, the estimated value of the position vector X of the target 20 X (hat), using the distance sum xi] _n (hat) at three receiving stations 3 a to 3 c, the conjugate gradient method, quasi-Newton method, Levenberg-Marquardt method, etc. It is obtained using a general non-linear method.
If the relative velocity vector of the target 20 is V, the linear equation of equation (13) can be rewritten into equation (15).
Then, the estimated value V (hat) of the relative velocity vector V of the target 20 is an inverse matrix or general inverse matrix from the relative velocity sum V _n (hat) and estimated value X (hat) at the three receiving stations 3a to 3c. It is calculated using.

  Such a target positioning device 1 uses FMCW radio waves as radio waves, and includes three or more receiving stations. The target positioning device 1 does not need to synchronize the time of the receiving station 3 with the time of the transmitting station 2, and can synchronize a pulser or a transmission pulse. Since no information is required, high-precision position resolution can be realized even in a narrow-band receiving system and a low-speed signal processing system, and the receiving station 3 can be made small and movable, thereby ensuring operational flexibility. Further, since the FMCW radio wave is used, the relative velocity can be estimated with high accuracy using the Doppler phenomenon.

Note that when the transmitting station 2 has a receiving function as well as a transmitting function, one of the three receiving stations 3 can be imposed on the transmitting station 2, so two receiving stations 3 are sufficient.
Further, when the two-dimensional estimation on the horizontal plane coordinates is performed for estimating the position coordinates and relative speed of the target 20, two receiving stations 3 may be used.
When the number of receiving stations 3 is two, the target position / velocity estimator 4 uses the two distance sums ξ _n obtained by the equation (13) to measure the position of the target 20 as the intersection of the spheroids. Is also possible. That is, the target 20 exists at the intersection of the two spheroids of the distance sum ξ _n with the transmitting station 2 and the receiving station 3 as the focal points, but by adding a constraint condition such as making the horizontal plane coordinate positive, The position coordinates of the target 20 can be estimated by selecting an appropriate solution as the position of the target 20 at the intersection of the two spheroids.

  In addition, FM pulses (also referred to as FMICW (FM Interrupted CW)) obtained by pulsing the FMCW, and distance gating, further narrowband, separation of direct and target reflected waves, separation of multiple targets, short-range clutter It can be avoided.

Embodiment 2. FIG.
FIG. 4 is a configuration diagram of a target positioning apparatus according to Embodiment 2 of the present invention. FIG. 5 is a diagram illustrating the positions of the transmitting station, the receiving station, and the target on the XY coordinate plane.
The target positioning device 1B according to the second embodiment of the present invention is the same as the target positioning device 1 according to the first embodiment except that the number of transmitting stations 2Ba to 2Bc and the number of receiving stations 3B are different. The same parts are denoted by the same reference numerals and the description thereof is omitted.
As shown in FIG. 4, the target positioning apparatus 1B according to the second embodiment includes three transmitting stations 2Ba to 2Bc and one receiving station 3B. The target positioning device 1B according to the second embodiment includes the three transmission stations 2Ba to 2Bc. However, the same effect can be obtained even if four or more transmission stations are provided.

The transmitting stations 2Ba to 2Bc, the receiving station 3B, and the target 20 are arranged as shown in FIG. When the coordinates of the receiving station 3B are placed at the origin of the XYZ coordinate system, the position vectors of the transmitting stations 2Ba to 2Bc are _Xn . n is a number for identifying the transmitting stations 2Ba to 2Bc. Since three transmitting stations 2Ba to 2Bc are provided, n = 1, 2, and 3. This position vector _Xn is known. The position vector X of the target 20 is an unknown value obtained by the target positioning device 1B.

  From each of the transmission stations 2Ba to 2Bc, transmission is time-divided in order to separate the three target reflected waves. Note that radio waves of FMCW signals having different center frequencies may be emitted for each of the transmission stations 2Ba to 2Bc, and the local signal of each FMCW signal may be mixed by the reception signal converter 10 of the reception station 3B.

As shown in FIG. 4, the FMCW signal processor 11 includes a target reflected wave frequency analyzing means 14, a direct wave frequency analyzing means 15, a time error estimating means 16, and a distance sum speed sum estimating means 17 as frequency analyzing means 13B. Have.
Assuming that the phase error δt _n caused by the time error of the FMCW signal between each of the transmitting stations 2Ba to 2Bc and the receiving station 3B, the target reflected beat signal B _{i, n} is expressed in the same manner as Expression (7).
Then, the target reflected wave frequency analyzing means 14 performs the Fourier transform on the target reflected beat signal B _{i, n} in the same manner as in the first embodiment _, and obtains the target reflected beat frequency f _{i, n} (bar) at which the output reaches a peak. It calculates | requires from Formula (9).

Similarly to the first embodiment, the direct wave frequency analyzing means 15 performs a Fourier transform on the direct beat signal B0 _{i, n} to obtain a direct beat frequency f0 _{i, n} (bar) at which the output reaches a peak (10). )

Using the target reflection beat frequency f _{i, n} (bar) and the direct beat frequency f0 _{i, n} (bar) obtained in this way, the estimated value X of the position vector of the target 20 as in the first embodiment. (Hat), an estimated value V (hat) of the relative velocity vector can be estimated.

If such a target positioning apparatus 1B includes three or more transmitting stations 2, it is not necessary to synchronize the time of the receiving station 3 with the time of the transmitting station 2 as in the first embodiment, and a synchronous pulser or transmission Since pulse information is not required, high-precision position resolution can be realized even in a narrow-band receiving system and a low-speed signal processing system, and the receiving station 3 can be made small and movable, thereby ensuring operational flexibility.
Even if the number of transmitting stations is 2, the position coordinates of the target 20 can be estimated by obtaining the intersection of the spheroids from the two distance sums ξ _n .

Embodiment 3 FIG.
FIG. 6 is a block diagram of a target positioning apparatus according to Embodiment 3 of the present invention. FIG. 7 is a diagram showing the positions of the transmitting station, the receiving station, and the target on the XY coordinate plane.
As shown in FIG. 6, the target positioning device 1C according to the third embodiment of the present invention receives signals common to the reception signal converters 10 of the three receiving stations 3a to 3c of the target positioning device 1 according to the first embodiment. Since the local signal is supplied from the FMCW signal generator 9 and the FMCW signal processor 11C is different in accordance with the local signal, the other parts are the same.
In the frequency analysis unit 13C according to the third embodiment, the direct wave frequency analysis unit 15 and the time error estimation unit 16 are deleted from the frequency analysis unit 13 according to the first embodiment.

The target positioning apparatus 1C according to the third embodiment receives only the target reflected wave as shown in FIG.
Each receiving station 3Ca-3Cc is connected by a cable 18 while adjusting the phase of the received FMCW signal from one received FMCW signal generator 9 to a constant value by correcting the delay caused by the difference in cable length. .

Since the received FMCW signal according to the third embodiment has the same phase between the receiving stations 3Ca to 3Cc, the time error δt _n of the transmitting station 2 and each of the receiving stations 3Ca to 3Cc is equal and becomes the time error δt. . Therefore, the target reflection beat signal Bi, n after being mixed by the reception signal converter 10 in each of the reception stations 3Ca to 3Cc is expressed by Expression (16).

The target reflected wave frequency analyzing means 14C performs a Fourier transform on the target reflected beat signal B _{i, n} and obtains a target reflected beat frequency f _{i, n} (bar) at which the output reaches a peak from the equation (17).
The distance sum speed sum estimating means 17C uses the detected target reflection beat frequency f _{i, n} (bar) to calculate the time between the transmitting station 2 and the target 20, the target 20, and the receiving stations 3Ca to 3Cc from the equation (18). A distance sum ξ _n (hat) including the error δt is obtained.
The distance sum speed sum estimating means 17C obtains the relative speed sum V _n (hat) from the equation (19).

The target position / speed estimator 4C estimates the three-dimensional coordinates and the three-dimensional relative speed component of the target 20 according to the following procedure.
If the position vector of the known transmitting station 2, the position vector of each known receiving station 3, and the position vector of the unknown target 20 to be estimated are X ₀ , X _n , and X, respectively, the distance sum ξ in equation (18) By using _n , Expressions (20) to (22) that can eliminate the time error δt are established.
Then, the estimated value X (hat) of the position vector X of the target 20 is calculated using the conjugate gradient method, the quasi-Newton method, the Levenberg-Marquardt method, etc. using the distance sum ξ _n (hat) at the three receiving stations 3Ca to 3Cc. It is obtained using a general non-linear method.

If the relative velocity vector of the target 20 is V, the linear equation of equation (19) can be rewritten into equation (23).
Then, the estimated value V (hat) of the relative velocity vector V of the target 20 is obtained by using an inverse matrix or a general inverse matrix using the relative velocity sum V _n (hat) and estimated value X (hat) at the three receiving stations 3. It is calculated using.

Such a target positioning apparatus 1C does not need to measure a direct wave because there is no time error difference between the received FMCW signals to the receiving stations 3Ca to 3Cc.
The same applies to a configuration in which a plurality of received FMCW signals are provided and they are time synchronized.

Embodiment 4 FIG.
FIG. 8 is a block diagram of a target positioning apparatus according to Embodiment 4 of the present invention. FIG. 9 is a diagram illustrating the positions of the transmitting station, the receiving station, and the target on the XY coordinate plane.
The target positioning device 1D according to the fourth embodiment of the present invention is supplied with the target positioning device 1B according to the second embodiment synchronized with the transmission FMCW signal, and accordingly, the FMCW signal processor 11D is different. Since the other parts are the same, the same reference numerals are attached to the same parts and the description thereof is omitted.
A target positioning apparatus 1D according to the fourth embodiment includes three transmitting stations 2Da to 2Dc and one receiving station 3D. Note that the target positioning apparatus 1D according to the fourth embodiment includes the three transmission stations 2Da to 2Dc, but the same effect can be obtained by including four or more transmission stations.
Each transmission station 2Da to 2Dc is connected by a cable 18 while the transmission FMCW signal from one transmission FMCW signal generator 5 is adjusted so that the phase of the transmission FMCW signal is corrected by correcting the delay due to the difference in cable length, etc. . Further, from each of the transmission stations 2Da to 2Dc, transmission is time-divided in order to separate the target reflected wave.

Since the transmission FMCW signal according to the fourth embodiment has the same phase between the transmission stations 2Da to 2Dc, the time error δt _n of each of the transmission stations 2Da to 2Dc and the reception station 3D is equal and becomes the time error δt. . Therefore, the target reflection beat signal B _{i, n} after being mixed by the reception signal converter 10 of the reception station 3D is expressed by Expression (16).

In the frequency analysis unit 13D according to the fourth embodiment, the direct wave frequency analysis unit 15 and the time error estimation unit 16 are deleted from the frequency analysis unit 13B according to the second embodiment.
The target reflected wave frequency analyzing means 14D performs a Fourier transform on the target reflected beat signal B _{i, n} and obtains a target reflected beat frequency f _{i, n} (bar) at which the output reaches a peak from the equation (17).

The distance sum speed sum estimating means 17D uses the detected target reflection beat frequency f _{i, n} (bar) to calculate the time error δt between each transmitting station 2 and the target 20, and between the target 20 and the receiving station 3 from the equation (18). A distance sum ξ _n (hat) including is obtained.
The distance sum speed sum estimating means 17D obtains the relative speed sum V _n (hat) from the equation (19).

The target position / speed estimator 4D estimates the three-dimensional coordinates and the three-dimensional relative speed component of the target 20 according to the following procedure.
When the position vector of the known receiving station 3D, the position vector of each of the known transmitting stations 2Da to 2Dc, and the position vector of the unknown target 20 to be estimated are X ₀ , X _n , and X, respectively, the distance of Expression (18) By using the sum ξ _n , Expressions (20) to (22) that can eliminate the time error δt are established.
Then, the estimated value X (hat) of the position vector X of the target 20 is calculated using the conjugate gradient method, the quasi-Newton method, the Levenberg-Marquardt method, etc. using the distance sum ξ _n (hat) from the three transmitting stations 2Da to 2Dc. It is obtained using a general non-linear method.

If the relative velocity vector of the target 20 is V, the linear equation of equation (19) can be rewritten into equation (23).
Then, the estimated value V (hat) of the relative velocity vector V of the target 20 is obtained by using an inverse matrix or generality using the relative velocity sum V _n (hat) and the estimated value X (hat) at the three transmission stations 2Da to 2Dc. It is obtained using an inverse matrix.

Such a target positioning apparatus 1D does not need to measure a direct wave because there is no time error difference between the FMCW signals transmitted to the transmitting stations 2Da to 2Dc.
The same applies to a configuration in which a plurality of transmission FMCW signals are provided and they are time synchronized.

Embodiment 5 FIG.
FIG. 10 is a block diagram of a target positioning apparatus according to Embodiment 5 of the present invention. FIG. 11 is a diagram showing the positions of the target transmitting station and receiving station on the XY coordinate plane.
A target positioning apparatus 1E according to Embodiment 5 of the present invention includes one transmitting station 2, three receiving stations 3Ea to 3Ec, and a target position / speed estimator 4E, and estimates the position and relative speed of the transmitting station 2. To do. The sum of distances and the sum of relative velocities obtained by the receiving stations 3Ea to 3Ec are sent to the target position / speed estimator 4E using communication means. Although the target positioning apparatus 1E according to the fifth embodiment includes the three receiving stations 3Ea to 3Ec, the same effect can be obtained by including four or more receiving stations.

In the target positioning apparatus 1E according to the fifth embodiment, the reception FMCW signal is supplied from the common reception FMCW signal generator 9 to the reception signal converters 10 of the three reception stations 3Ea to 3Ec. Each receiving station 3Ea to 3Ec is connected by a cable 18 while the received FMCW signal from one received FMCW signal generator 9 is adjusted so as to correct the delay due to the difference in cable length and the phase is adjusted to a constant value. . Since the received FMCW signal according to the fifth embodiment has the same phase between the receiving stations 3Ea to 3Ec, the time error δt _n of the transmitting station 2 and each of the receiving stations 3Ea to 3Ec is equal and becomes the time error δt. .

Since the transmitting station 2 is the same as the transmitting station 2 according to the first embodiment, description thereof is omitted. The radio Tx _i emitted is represented by the formula (24).

  Each of the receiving stations 3Ea to 3Ec receives a radio wave that arrives by propagating through the air, mixes the received FMCW signal with the received radio wave, removes a sum signal of frequencies by a low-pass filter, and generates a beat signal A reception signal converter 10 for processing the beat signal, and an FMCW signal processor 11E for estimating the sum of distance and relative speed. The receiving station 3Ea also includes a reception FMCW signal generator 9 that generates a reception FMCW signal, and a cable 18 is connected to the reception signal converter 10.

The radio wave radiated from the transmitting antenna 7 into the air directly reaches the receiving antenna 8. In the following description, radio waves that reach directly are referred to as direct waves. The direct wave Rx0 _{i, n} is expressed by Expression (25). Note that τ _0n is a propagation time during which the radio wave propagates between the transmitting station and the receiving station, and the relationship R _0n between the transmitting station and the receiving station and the relational expression (26) are established.

The reception FMCW signal generator 9 generates a reception FMCW signal that generates a local signal for mixing the received direct wave in the reception signal converter 10, generates a local signal using the reception FMCW signal, and receives the reception signal. Output to the converter 10.
The local signal L _{i, n} generated by the reception FMCW signal generator 9 is expressed by Expression (27).

The reception signal converter 10 mixes the direct wave Rx0 _{i, n} with the local signal L _{i, n} , passes through the low-pass filter, removes the frequency sum signal, and directly obtains the beat signal B0 _{i, n} . The direct beat signal B0 _{i, n} is expressed by equation (28).

The FMCW signal processor 11E has a direct wave frequency analysis means 15 and a distance sum speed sum estimation means 17E as the frequency analysis means 13E.
The direct wave frequency analyzing means 15E performs a Fourier transform on the direct beat signal B0 _{i, n} and obtains a direct beat frequency f0 _{i, n} (bar) at which the output reaches a peak from the equation (29).

The distance sum speed sum estimation means 17E uses the detected direct beat frequency f0 _{i, n} (bar) to calculate the time error δt between the transmitting station 2 and the target 20 and between the target 20 and each receiving station 3 from the equation (30). A distance sum ξ _n (hat) including is obtained.
Further, the distance sum speed sum estimating means 17E obtains the relative speed sum Vn (hat) from the equation (31).

The target position / speed estimator 4E estimates the three-dimensional coordinates and the three-dimensional relative speed component of the target transmission station 2 according to the following procedure.
Assuming that the position vector of the unknown transmitting station 2E to be estimated and the position vector of each known receiving station 3 are X and _Xn , respectively, the time error δt is eliminated by using the distance sum ξ _n of equation (30). The following relational expressions (32) to (34) hold.
Then, the estimated value X (hat) of the position vector X of the transmitting station 2 is calculated using the conjugate gradient method, the quasi-Newton method, the Levenberg-Marquardt, using the distance sum ξ _n (hat) at the three receiving stations 3Ea to 3Ec. It is obtained by using a general nonlinear method such as the method.

Further, when the relative velocity vector of the transmitting station 2 is V, the relative velocity vector V satisfies the relational expression (35).
Then, the estimated value V (hat) of the relative velocity vector V of the transmitting station 2 is obtained by using the relative velocity sum V _n (hat) and the estimated value X (hat) at the three receiving stations 3Ea to 3Ec, It is obtained using a general inverse matrix.

  Such a target positioning apparatus 1E needs to synchronize the time of the receiving stations 3Ea to 3Ec with the time of the transmitting station 2 in the operation mode in which the target to be estimated is the transmitting station 2 as in the first embodiment. Since no synchronization pulser or transmission pulse information is required, high-accuracy position resolution can be realized even in a narrow-band reception system and a low-speed signal processing system, resulting in small and mobile reception stations 3Ea to 3Ec. , Ensure operational flexibility.

Embodiment 6 FIG.
FIG. 12 is a block diagram of a target positioning apparatus according to Embodiment 6 of the present invention. FIG. 13 is a diagram showing the positions of the target receiving station and transmitting station on the XY coordinate plane.
A target positioning apparatus 1F according to Embodiment 6 of the present invention includes three transmitting stations 2Fa to 2Fc, one receiving station 3F, and a target position / speed estimator 4F, and estimates the position and relative speed of the receiving station 3F. To do. The distance sum and the relative speed sum obtained at the receiving station 3F are sent to the target position / speed estimator 4F using the communication means. The target positioning apparatus 1F according to the sixth embodiment includes the three transmission stations 2Fa to 2Fc, but the same effect can be obtained even if four or more transmission stations are provided.

In the target positioning apparatus 1F according to the sixth embodiment, the transmission FMCW signal is supplied from the common transmission FMCW signal generator 5 to the transmission signal converters 6 of the three transmission stations 2Fa to 2Fc. Each transmission station 2Fa to 2Fc is connected by a cable 18 while the transmission FMCW signal from one transmission FMCW signal generator 5 is adjusted so as to correct the delay due to the difference in cable length and the phase is adjusted to a constant value. . Since the transmission FMCW signal according to the sixth embodiment has the same phase between the transmission stations 2Fa to 2Fc, the time errors δt _n of the transmission stations 2Fa to 2Fc and the reception station 3F are equal and become the time error δt.

The reception FMCW signal generator 9 generates a reception FMCW signal that generates a local signal for mixing the received direct wave in the reception signal converter 10, generates a local signal using the reception FMCW signal, and receives the reception signal. Output to the converter 10.
The local signal L _{i, n} generated by the reception FMCW signal generator 9 is expressed by Expression (27).

The reception signal converter 10 mixes the direct wave Rx0 _{i, n} with the local signal L _{i, n} , passes through the low-pass filter, removes the frequency sum signal, and directly obtains the beat signal B0 _{i, n} . The direct beat signal B0 _{i, n} is expressed by equation (28).

The direct wave frequency analyzing means 15F performs a Fourier transform on the direct beat signal B0 _{i, n} and obtains a direct beat frequency f0 _{i, n} (hat) at which the output reaches a peak from the equation (29).

The distance sum speed sum estimating means 17F uses the detected direct beat frequency f0 _{i, n} (hat) to calculate the distance between the transmitting stations 2Fa to 2Fc and the target 20 and the distance between the target 20 and the receiving station 3 from the equation (30). The sum ξ _n (hat) is obtained.
The distance sum speed sum estimating means 17F obtains the relative speed sum Vn (hat) from the equation (31).

The target position / speed estimator 4F estimates the three-dimensional coordinates and the three-dimensional relative speed component of the receiving station 3F according to the following procedure.
Assuming that the position vector of the unknown receiving station 3F to be estimated and the position vectors of the known transmitting stations 2Fa to 2Fc are X and _Xn , respectively, the time error δt is obtained by using the distance sum ξ _n of Equation (30). Is deleted, and the relational expressions (32) to (34) are established.
Then, the estimated value X (hat) of the position vector X of the receiving station 3F is obtained using the conjugate gradient method, quasi-Newton method, and Levenberg-Marquardt method using the distance sum ξ _n (hat) with the three transmitting stations 2Fa to 2Fc. It is calculated | required using general nonlinear methods, such as.

When the relative velocity vector of the receiving station 3F is V, the relative velocity vector V satisfies the relational expression (35).
Then, the estimated value V (hat) of the relative velocity vector V of the receiving station 3F is obtained by using the relative velocity sum V _n (hat) and the estimated value X (hat) at the three transmitting stations 2Fa to 2Fc, It is obtained using a general inverse matrix.

  Such a target positioning device 1F does not need to synchronize the time of the transmitting stations 2Fa to 2Fc with the time of the receiving station 3F even in an operation mode in which the target for estimating the position and velocity is the receiving station 3F. And transmission pulse information is not required, so it is possible to achieve high-precision position resolution even in narrow-band reception systems and low-speed signal processing systems. it can.

Embodiment 7 FIG.
FIG. 14 is a block diagram of a target positioning apparatus according to Embodiment 7 of the present invention. FIG. 15 is a diagram illustrating changes in the frequency of the FMCW signal at the transmitting station and the receiving station.
The target positioning apparatus 1G according to the seventh embodiment of the present invention is different from the target positioning apparatus 1 according to the first embodiment in the FMCW signal and receives the target reflected wave and the direct wave at the receiving stations 3Ga to 3Gc without separating them. The other parts are the same, and the other parts are the same. Further, the positions and relative speeds of the transmitting station 2G, the receiving stations 3Ga to 3Gc, and the target 20 are the same as those in FIG.
The target positioning device 1G according to the seventh embodiment is applied to target positioning when the receiving stations 3Ga to 3Gc receive the direct wave from the transmitting station 2G and the target reflected wave without being separated. However, the target positioning apparatus 1G according to the seventh embodiment can be applied when the relative speed τ _0n between the transmitting station and the receiving station is known.

Transmitting FMCW signal generator 5G, as shown in FIG. 15 (a), the sweep slope mu _1, sweep gradient _μ 2 = _{-μ 1,} transmission FMCW three sweep time frequency pattern _{which T C} is continuous sweep slope zero Generate a signal.
As shown in FIG. 15B, the reception FMCW signal generator 9G generates a reception FMCW signal having a frequency pattern obtained by shifting the transmission FMCW signal by a time shift δt _n and generates a local signal based on the reception FMCW signal. , And transmitted to the received signal converter 10.
The reception signal converter 10 mixes the received radio wave signal with a local signal, removes the sum signal of frequencies by a low-pass filter, and obtains a beat signal.
The frequency analyzing means 19 performs Fourier transform on the beat signal and detects two beat frequencies at which the output reaches a peak. These two beat frequencies can be expressed by Expression (36) and Expression (37). However, it cannot be distinguished which of the beat frequencies relates to the direct wave or the target reflected wave.

Therefore, the distance sum speed sum estimating means 17G obtains the absolute value of the difference between the beat frequencies as shown in the equations (38) and (39), so that the propagation time τ ₀ between the transmitting station 2G and the target 20 and the target are obtained. 20 and the sum (τ ₀ + τ _n ) of the propagation time τ _n between each of the receiving stations 3Ga to 3Gc, the relative velocity v ₀ between the transmitting station 2G and the target 20, the target 20, and each of the receiving stations 3Ga to 3Gc. the sum of the relative velocity _{v n (v 0 + v n} ) can be obtained. In this operation mode, the relative speed τ _0n between the transmitting station 2G and the receiving stations 3Ga to 3Gc is known, and the positions of the transmitting station 2G and the receiving stations 3Ga to 3Gc are also known.

By obtaining the observation values of Equation (38) and Equation (39), for example, in a monostatic radar capable of measuring only an In-phase channel (real beat signal), the literature (Three books, “In-phase signal”). FMCW radar target distance / velocity measurement method that detects only the frequency ”, the Institute of Electronics, Information and Communication Engineers, Journal B, Vol. J82-B, No. 12, p. 2355-2363, December 1999) The distance sum ξ _n = c (τ ₀ + τ _n ) and the relative velocity sum V _n (hat) can be obtained by a method of removing the relative velocity ambiguity (at one target).
As in the first embodiment, the position coordinate and relative speed of the target 20 can be estimated from the distance sum ξ _n = c (τ ₀ + τ _n ) and the relative speed sum V _n (hat).

  Such a target positioning apparatus 1G employs a pattern in which frequency sweeping is not performed in part as the FMCW signal, so that the distance sum and the relative speed sum can be obtained from the absolute value of the difference between the beat signals. Even when reception of waves and target reflected waves cannot be separated, the target position coordinates and relative velocity can be estimated.

Embodiment 8 FIG.
FIG. 16 is a block diagram of a target positioning apparatus according to Embodiment 8 of the present invention.
The target positioning apparatus 1H according to the eighth embodiment of the present invention is different from the target positioning apparatus 1B according to the second embodiment in the FMCW signal and receives the target reflected wave and the direct wave at the receiving station 3H without separating them. Are the same, and the other parts are the same. Therefore, the same reference numerals are attached to the same parts and the description thereof is omitted. Further, the positions and relative speeds of the transmitting stations 2Ha to 2Hc, the receiving station 3H, and the target 20 are the same as those in FIG.
The target positioning apparatus 1H according to the eighth embodiment is applied to target positioning when the receiving station 3H receives the direct wave and the target reflected wave from the transmitting stations 2Ha to 2Hc without being separated. However, the target positioning device 1H according to the eighth embodiment can be applied when the relative speed τ _0n between the transmitting stations 2Ha to 2Hc and the receiving station 3H is known.

Transmitting FMCW signal generator 5H, as shown in FIG. 15 (a), the sweep slope mu _1, sweep gradient _μ 2 = _{-μ 1,} transmission FMCW three sweep time frequency pattern _{which T C} is continuous sweep slope zero Generate a signal.
As shown in FIG. 15B, the reception FMCW signal generator 9H generates a reception FMCW signal having a frequency pattern obtained by shifting the transmission FMCW signal by a time shift δt _n and generates a local signal based on the reception FMCW signal. , And transmitted to the received signal converter 10.
The reception signal converter 10 mixes the received radio wave signal with a local signal, removes the sum signal of frequencies by a low-pass filter, and obtains a beat signal.
The frequency analyzing means 19 performs Fourier transform on the beat signal and detects two beat frequencies at which the output reaches a peak. These two beat frequencies can be expressed by Expression (36) and Expression (37). However, it cannot be distinguished which of the beat frequencies relates to the direct wave or the target reflected wave.

Therefore, the distance sum speed sum estimating means 17H obtains the absolute value of the difference between the beat frequencies as shown in the equations (38) and (39), so that the propagation time τ _n between the transmitting stations 2Ha to 2Hc and the target 20 is obtained. the relative speed between the sum of the propagation time tau ₀ between the receiving station 3H target _{20 (τ 0 + τ n)} , and the relative velocity _{v n} and the target 20 in the transmitting station 2Ha~2Hc and the target 20 and the receiving station 3H v ₀ the sum of _(v 0 + v _n) can be obtained. In this operation mode, the relative speed τ _0n between the transmitting stations 2Ha to 2Hc and the receiving station 3H is known, and the positions of the transmitting stations 2Ha to 2Hc and the receiving station 3H are also known.

By obtaining the observation values of Equation (38) and Equation (39), for example, in a monostatic radar capable of measuring only an In-phase channel (real beat signal), the literature (Three books, “In-phase signal”). FMCW radar target distance / velocity measurement method that detects only the frequency ”, the Institute of Electronics, Information and Communication Engineers, Journal B, Vol. J82-B, No. 12, p. 2355-2363, December 1999) The distance sum ξ _n = c (τ ₀ + τ _n ) and the relative velocity sum V _n (hat) can be obtained by a method of removing the relative velocity ambiguity (at one target).
As in the first embodiment, the position and relative speed of the target 20 can be estimated from the distance sum ξ _n = c (τ ₀ + τ _n ) and the relative speed sum V _n (hat).

  Since the target positioning device 1H employs a pattern in which frequency sweep is not performed in part as the FMCW signal, the distance sum and the relative speed sum can be obtained from the absolute value of the difference between the beat signals. Even when the reception of the wave and the target reflected wave cannot be separated, the target position and relative velocity can be estimated.

  It should be noted that the distance sum speed sum estimation means in Embodiments 1 to 8 can be combined with the target position estimation method in the case where angle measurement can be performed at the receiving station.

It is a block diagram of the target positioning apparatus concerning Embodiment 1 of this invention. It is a figure which shows the position on the XY coordinate plane of a transmitting station, a receiving station, and a target. It is a figure which shows the mode of the change of the frequency of the FMCW signal in a transmitting station and a receiving station. It is a block diagram of the target positioning apparatus concerning Embodiment 2 of this invention. It is a figure which shows the position on the XY coordinate plane of a transmitting station, a receiving station, and a target. It is a block diagram of the target positioning apparatus concerning Embodiment 3 of this invention. It is a figure which shows the position on the XY coordinate plane of a transmitting station, a receiving station, and a target. It is a block diagram of the target positioning apparatus concerning Embodiment 4 of this invention. It is a figure which shows the position on the XY coordinate plane of a transmitting station, a receiving station, and a target. It is a block diagram of the target positioning apparatus concerning Embodiment 5 of this invention. It is a figure which shows the position on the XY coordinate plane of the transmission station and receiving station which are targets. It is a block diagram of the target positioning apparatus concerning Embodiment 6 of this invention. It is a figure which shows the position on the XY coordinate plane of the receiving station and transmitting station which are targets. It is a block diagram of the target positioning apparatus concerning Embodiment 7 of this invention. It is a figure which shows the mode of the change of the frequency of the FMCW signal in a transmitting station and a receiving station. It is a block diagram of the target positioning apparatus concerning Embodiment 8 of this invention.

Explanation of symbols

  1 target positioning device, 2 transmitting station, 3 receiving station, 4 target position / speed estimator, 5 transmitting FMCW signal generator, 6 transmitting signal converter, 7 transmitting antenna, 8 receiving antenna, 9 receiving FMCW signal generator, 10 Received signal converter, 11 FMCW signal processor, 13, 19 Frequency analysis means, 14 Target reflected wave frequency analysis means, 15 Direct wave frequency analysis means, 16 Time error estimation means, 17 Distance sum speed sum estimation means, 18 Cable, 20 Goal.

Claims (9)

Transmitting station that emits radio waves, three or more receiving stations that receive radio waves that arrive directly or after being reflected by the target object, and target position / speed estimation that estimates the target position and speed based on the received radio waves In the target positioning device comprising a device,
The transmitter station
A transmission FMCW signal generator for generating a transmission FMCW signal;
A transmission signal converter for modulating radio waves with the transmission FMCW signal;
With
The receiving station is
A received FMCW signal generator that generates a local signal with a sweep slope and sweep time similar to the FMCW signal;
A reception signal converter for obtaining a beat signal by mixing the radio wave received from the transmission station and the local signal;
Frequency analysis means for calculating the beat frequency and time error at which the output of the beat signal is maximized;
Distance sum speed sum estimation means for estimating a sum of distances and a relative speed sum between the transmitting station and the receiving station based on the beat frequency and the time error;
With
The target position / speed estimator estimates a three-dimensional position coordinate of the target based on the distance sum input from the receiving station and the time error, and calculates the three-dimensional position coordinate and the relative speed sum. A target positioning apparatus characterized by estimating a three-dimensional relative velocity component of the target based on the target. The reception signal converter mixes the radio wave received directly from the transmitting station or the radio wave received after being reflected at the target and the local signal to obtain a direct beat signal or target reflected beat signal,
The frequency analyzing means includes a direct wave frequency analyzing means for calculating a direct beat frequency at which the output of the direct beat signal is maximized, and a target reflected wave for calculating a target reflected beat frequency at which the output of the target reflected beat signal is maximized. A frequency analysis means, and a time error estimation means for estimating a time error based on the direct beat frequency,
The distance sum speed sum estimating means estimates the distance sum and relative speed sum between the transmitting station and the receiving station based on the target reflection beat frequency and the time error. Target positioning device to be described. A reception FMCW signal synchronized with the reception FMCW signal supplied to the reception signal converters of the other reception stations is supplied to the reception signal converter of each of the reception stations, and is received after being reflected by the target. To obtain the target reflection beat signal by mixing the radio signal and the local signal
The frequency analyzing means includes target reflected wave frequency analyzing means for calculating a target reflected beat frequency at which the output of the target reflected beat signal is maximized,
The distance sum speed sum estimating means estimates a distance sum and a relative speed sum including a time error between the transmitting station and the receiving station based on the target beat frequency calculated by the target reflected wave frequency analyzing means,
The target position / speed estimator estimates the three-dimensional position coordinates of the target by erasing the time error from the distance sum including the time error input from the receiving station, and the three-dimensional position coordinate and the relative position 2. The target positioning apparatus according to claim 1, wherein a three-dimensional relative speed of the target is estimated based on a speed sum. A reception FMCW signal synchronized with the reception FMCW signal supplied to the reception signal converter of the other reception station is supplied to the reception signal converter of each of the reception stations, and is received directly from the transmission station. The beat signal is obtained directly by mixing the radio wave and the local signal,
The frequency analysis means includes direct wave frequency analysis means for calculating a direct beat frequency at which the output of the direct beat signal is maximized,
The distance sum speed sum estimating means estimates a distance sum and a relative speed sum including a time error between the transmitting station and the receiving station based on the direct beat frequency calculated by the direct wave frequency analyzing means,
The target position / speed estimator estimates the three-dimensional position coordinates of the transmitting station by erasing the time error from the distance sum including the time error input from the receiving station, and the three-dimensional position coordinates and the 2. The target positioning device according to claim 1, wherein a three-dimensional relative speed of the transmitting station is estimated based on a relative speed sum. Three or more transmitting stations that radiate radio waves, a receiving station that receives radio waves that arrive directly or after being reflected by the target, and a target position / speed that estimates the target position coordinates and relative speed based on the received radio waves In a target positioning device comprising an estimator,
The transmitter station
A transmission FMCW signal generator for generating a transmission FMCW signal;
A transmission signal converter for modulating radio waves with the transmission FMCW signal;
With
The receiving station is
A received FMCW signal generator that generates a local signal with a sweep slope and sweep time similar to the FMCW signal;
A reception signal converter for obtaining a beat signal by mixing the radio wave received from the transmitting station and the local signal;
Frequency analysis means for calculating the beat frequency and time error at which the output of the beat signal is maximized;
Distance sum speed sum estimating means for estimating a sum of distances and a relative speed sum between the transmitting station and the receiving station based on the beat frequency and the time error;
With
The target position / speed estimator estimates a three-dimensional position coordinate of the target based on the distance sum input from the receiving station and the time error, and calculates the three-dimensional position coordinate and the relative speed sum. A target positioning apparatus characterized by estimating a three-dimensional relative velocity component of the target based on the target. The reception signal converter obtains a direct beat signal or a target reflection beat signal by mixing a radio wave directly received from each transmitting station or a radio wave received after being reflected by a target and the local signal,
The frequency analyzing means includes a direct wave frequency analyzing means for calculating a direct beat frequency at which the output of the direct beat signal is maximized, and a target reflected wave for calculating a target reflected beat frequency at which the output of the target reflected beat signal is maximized. A frequency analysis means, and a time error estimation means for estimating a time error based on the direct beat frequency,
6. The distance sum speed sum estimating means estimates a distance sum and a relative speed sum between the transmitting station and the receiving station based on the target reflection beat frequency and the time error. Target positioning device to be described. A transmission FMCW signal synchronized with the transmission FMCW signal supplied to the transmission signal converter of the other transmission station is supplied to the transmission signal converter of each of the transmission stations,
The reception signal converter mixes a radio wave received after being reflected by the target and the local signal to obtain a target reflected beat signal,
The frequency analyzing means includes target reflected wave frequency analyzing means for calculating a target reflected beat frequency at which the output of the target reflected beat signal is maximized,
The distance sum speed sum estimating means estimates a distance sum and a relative speed sum including a time error between the transmitting station and the receiving station based on the target beat frequency calculated by the target reflected wave frequency analyzing means,
The target position / speed estimator estimates the three-dimensional position coordinates of the target by erasing the time error from the distance sum including the time error input from the receiving station, and the three-dimensional position coordinate and the relative position 6. The target positioning apparatus according to claim 5, wherein a three-dimensional relative speed of the target is estimated based on a speed sum. A transmission FMCW signal synchronized with the transmission FMCW signal supplied to the transmission signal converter of the other transmission station is supplied to the transmission signal converter of each of the transmission stations,
The reception signal converter obtains a beat signal directly by mixing a radio wave directly received from each transmitting station and the local signal,
The frequency analysis means includes direct wave frequency analysis means for calculating a direct beat frequency at which the output of the direct beat signal is maximized,
The distance sum speed sum estimating means estimates a distance sum and a relative speed sum including a time error between the transmitting station and the receiving station based on the direct beat frequency calculated by the direct wave frequency analyzing means,
The target position / speed estimator estimates a three-dimensional position coordinate of the receiving station by erasing the time error from a distance sum including the time error input from the receiving station, and the three-dimensional position coordinate and the 6. The target positioning apparatus according to claim 5, wherein a three-dimensional relative speed of the receiving station is estimated based on a relative speed sum. The transmission FMCW signal and the reception FMCW signal include a time during which the frequency is kept constant,
The distance between the transmitting station and the receiving station is known;
The frequency analysis means calculates two beat frequencies from the beat signal,
The distance sum speed sum estimation means estimates a distance sum and a relative speed sum between the transmitting station and the receiving station based on an absolute value of a difference between two beat frequencies. 5. The target positioning device described in 5.

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