JP5606151B2 - Radar equipment - Google Patents

Description

  The present invention relates to a radar apparatus.

  Conventionally, for example, in Non-Patent Document 1 below, a multi-static radar observes a target distance (time) and a Doppler frequency so that a target three-dimensional or two-dimensional position vector and velocity are obtained by positioning and speed measurement calculations. What estimates a vector is described. Such multi-static radar positioning and speed measurement processing uses multiple pieces of target distance (time) and Doppler frequency information, so positioning with higher accuracy and instantaneous speed vector estimation can be performed. .

K. C. HO: “An Accurate Algebraic Solution for Moving Source Location Using TDOA and FDOA Measurements”, IEEE Trans. On Signal Processing, Vol.52, No.9, Sep. 2004

  In the positioning and speed measurement processing with multistatic radar using the reception time and Doppler frequency as described above, when there are a plurality of targets, the reception signal corresponding to each target is determined from the plurality of reception signals at each observation point. There was a problem that correct positioning and speed measurement results could not be obtained because the combination could not be known.

  The present invention has been made to solve the above-described problems, and provides a radar apparatus that can solve the problem of a combination of received signals and realize highly accurate positioning and speed measurement processing for each of a plurality of targets. The purpose is that.

The present invention is for receiving a radio wave reflected from a plurality of targets located at different observation points and a transmission unit that radiates radio waves, and observing a reception time and a Doppler frequency for each target. A plurality of receiving units each having a time / Doppler frequency sensor and an angle measuring sensor for observing the direction of each target, and a target position from the reception time, Doppler frequency and angle measuring value observed by each receiving unit. A positioning / speed measurement computing unit including a first means for estimating the position and speed of the plurality of targets by estimating a vector and a velocity vector, wherein the first means of the positioning / speed measurement computing unit has a plurality of targets In this case, the reception time calculation value at each reception unit calculated from the target position vector candidate obtained from the angle measurement value observed at each reception unit is compared with the reception time observation value observed at each reception unit. And in, to determine the combination of received time observations and Doppler frequency observed values among the receiving unit, estimates the position and velocity vectors of each of the plurality targets in the radar apparatus and the like, characterized in that.

  According to the present invention, it is possible to provide a radar apparatus that can solve the problem of the combination of received signals and realize highly accurate positioning and speed measurement processing for each of a plurality of targets.

It is a figure which shows schematic structure of the radar apparatus by this invention. It is a figure which shows the observation system arrangement | positioning of the radar apparatus by Embodiment 1 of this invention. It is a figure which shows the relationship between the target position in the structure of FIG. 2, and reception time information. It is a figure which shows the relationship between the target position and the angle measurement value in the structure of FIG. It is a figure which shows the flow of the process by an example of the positioning and speed measurement calculating part of the radar apparatus by Embodiment 1 of this invention with a functional block. It is a figure which shows the flow of a process by another example of the positioning and speed measurement calculating part of the radar apparatus by Embodiment 1 of this invention with a functional block. It is a figure which shows the flow of the process by another example of the positioning and speed measurement calculating part of the radar apparatus by Embodiment 1 of this invention with a functional block. It is a figure which shows an example of the observation timing of the time and frequency sensor of a radar apparatus by Embodiment 2 of this invention, and an angle measurement sensor. It is a figure which shows the flow of a process by an example of the positioning and speed measurement calculating part of the radar apparatus by Embodiment 2 of this invention with a functional block. It is a figure which shows the relationship between the reception time at the time of the false alarm which concerns on the radar apparatus by Embodiment 3 of this invention, and a target position. It is a figure which shows the relationship between the angle measurement value at the time of a false alarm which concerns on the radar apparatus by Embodiment 3 of this invention, and a target position. It is a figure which shows the relationship between the assumption target number which concerns on the radar apparatus by Embodiment 3 of this invention, and the magnitude | size of the minimum value of an evaluation function. It is a figure which shows the flow of a process by an example of the positioning and speed measurement calculating part of the radar apparatus by Embodiment 3 of this invention with a functional block. It is a figure which shows the flow of a process by an example of the positioning and speed measurement calculating part of the radar apparatus by Embodiment 4 of this invention with a functional block. It is a figure which shows the transmission / reception form of the observation system in the case of a single target. It is a figure which shows the transmission / reception form of the observation system in the case of multiple targets. It is the figure which showed the mode of the received signal in each observation point in the case of multiple targets on the time-frequency domain.

  First, the problem when there are multiple targets will be described in a little more detail. When there are a plurality of targets, a plurality of times and Doppler frequencies are observed for each observation point. For this reason, it is necessary to determine the combination of observation values used when estimating the position vector and velocity vector of each target. If an incorrect combination of observation values is used, the target position vector and velocity vector are correctly estimated. Can not.

  Hereinafter, with reference to FIGS. 15 to 17, the positioning and speed measurement method in the case of a single target will be described, and then the problems in the case of a plurality of targets will be described.

  FIG. 15 shows a transmission / reception mode of a general observation system in the case of a single target, and shows a configuration for performing two-dimensional positioning and speed measurement processing. The radio wave radiated from the radio wave source 1 is reflected by the target 4, and the observation point 2 and the observation point 3 receive the reflected wave. The radio wave source 1, the observation point 2, and the observation point 3 are time-synchronized by means such as GPS or use of direct waves from the radio wave source 1 to the observation point 2 and the observation point 3. Information on the reception time and Doppler frequency observed from the received wave is collected in one place, that is, a positioning / speed measurement calculation unit (not shown), and positioning / speed measurement calculation processing is performed.

  The following relational expressions (1) to (4) are established between the reception time and Doppler frequency observed at the observation point 2 and the observation point 3 and the target position vector and velocity vector.

However,
p: position vector v: velocity vector
(Subscripts 2, 3, S, T indicate observation point 2, observation point 3, radio source, and target)
τ _n : reception time observed at observation point n f _n : Doppler frequency observed at observation point n c: radio wave propagation speed f ₀ : transmission frequency.

  In the positioning / speed measurement calculation process, these two equations (1) to (4) are solved for the target position vector and the target velocity vector, thereby estimating the target two-dimensional position and velocity vector. This simultaneous equation is a nonlinear equation, but can be solved by an iterative improvement method (Gauss-Newton method) using linear approximation.

  Further, in the case of FIG. 15, the configuration is based on the estimation of the two-dimensional target position vector and velocity vector, but it is also possible to estimate the three-dimensional target position vector and velocity vector by increasing the number of observation points. it can. At this time, equations for the reception time and the Doppler frequency at the increased observation point are added to the positioning and speed measurement equations of Equations (1) to (4), and simultaneous equations for the three-dimensional target position vector and the three-dimensional target velocity vector are obtained. solve.

  However, when there are a plurality of targets, the transmission / reception mode of the observation system is as shown in FIG. In FIG. 16, similarly to FIG. 15, radio waves are radiated from the radio wave source 1, but since there are two targets 4A and 4B, the observation point 2 and the observation point 3 are both from the target 4A and the target 4B. Receive reflected waves.

  FIG. 17 shows the state of the received signal on the time-frequency domain at the observation point 2 and the observation point 3 at this time. In FIG. 17, two received signals exist on the time-frequency domain at both the right observation point 2 and the left observation point 3. The positioning / speed measurement calculation processing is performed for each combination of the received signals corresponding to the target 4A and the combination corresponding to the target 4B among the two received signals of the received signals of the observation point 2 and the observation point 3, respectively. This is done by solving (4). However, if the combination of received signals is incorrect, correct positioning and speed measurement results cannot be obtained. Therefore, it becomes a problem to solve the combination problem of received signals corresponding to the target of positioning and speed measurement.

  In the present invention, the problem of combining received signals between observation points is solved, positioning and speed measurement processing are performed for each of a plurality of targets, and the target reflected wave does not exist in the received signals at each observation point. When a false alarm that misidentifies that it exists, it is possible to perform positioning and speed measurement processing of multiple targets.

  In this invention, each observation point has an angle measurement sensor for observing the target direction in addition to the sensor for observing the reception time and the Doppler frequency, and information on the target position vector based on the angle measurement value of the angle measurement sensor; By comparing the information on the target position vector according to the reception time, the combination problem of the received signals is solved, and highly accurate positioning and speed measurement processing are realized for each of the plurality of targets.

  Hereinafter, a radar device according to the present invention will be described with reference to the drawings according to each embodiment. In each embodiment, the same or corresponding parts are denoted by the same reference numerals, and redundant description is omitted.

Embodiment 1 FIG.
FIG. 1 is a diagram showing a schematic configuration of a radar apparatus according to the present invention. For example, the positioning / speed measurement calculation unit C is provided with a transmission unit 100 provided with a transmission antenna AN as a radio wave source 1, and a time / Doppler frequency sensor TDS and an angle measurement sensor AS provided at observation points 2A and 3A, respectively. Two receiving units 200 and 300 are connected to be communicable by wire or wirelessly. The transmission unit 100 and the reception units 200 and 300 are time-synchronized by means such as GPS and use of direct waves from the transmission unit 100 to the reception units 200 and 300. It should be noted that the number of observation points, ie, receivers, is configured to be two or more when obtaining the target two-dimensional position and velocity, and three or more when obtaining the target three-dimensional position and velocity. Further, the positions of the transmission unit 100 and the reception units 200 and 300 are stored in advance in a storage unit (not shown) of the positioning / speed measurement calculation unit C when they are fixed, and when they are movable, It is assumed that the position information is sequentially sent, for example, attached to each observation information. In the following description, in order to facilitate the understanding of the invention, the description on the position information of the transmission unit 100 and the reception units 200 and 300 is omitted (for example, it is considered to be fixed at a known position).

  FIG. 2 is a diagram showing the observation system arrangement of the radar apparatus according to Embodiment 1 of the present invention. The observation system in FIG. 2 is assumed to perform two-dimensional positioning and speed measurement processing as in FIG. In FIG. 2, similarly to FIG. 16, radio waves are radiated from the radio wave source 1 corresponding to the transmission unit 100 provided with the transmission antenna AN for the two targets 4A and 4B. Observation points 2A and 3A corresponding to reception units 200 and 300 respectively receive reflected waves from these targets and observe reception times and Doppler frequencies. However, in the observation point 2A and the observation point 3A in the present invention, as shown in the receiving units 200 and 300 in FIG. 1, respectively, for the time / Doppler frequency comprising an RF (Radio Frequency) sensor for obtaining the reception time and the Doppler frequency. Apart from a sensor (hereinafter referred to as a time / frequency sensor) TDS, an angle measuring sensor AS for observing a target azimuth is provided. Examples of the angle measuring sensor AS include an RF angle measuring sensor and an IR (Infrared) sensor. At this time, since the sensors are different for the observation values at the plurality of reception times and the plurality of angle measurement values, it is not known which reception time and which angle measurement value correspond to the same target. Under such circumstances, the concept of the present invention is to solve the received signal combination problem between the observation points by comparing the estimation result candidates of the target position vector including the incorrect combination with respect to the reception time and the angle measurement value. It becomes.

  FIG. 3 shows a relationship diagram between the target position and the reception time information in the configuration of FIG. In FIG. 3, two curves drawn with broken lines represent isochronous curves drawn from the observation value of the reception time obtained by the time / frequency sensor TDS at the observation point 2A. Similarly, two curves drawn by a one-dot chain line represent isochronous curves drawn from the observation value of the reception time obtained by the time / frequency sensor TDS at the observation point 3A. The positioning process using the reception time information at a plurality of observation points means searching for the intersection of these curves. Looking at the position of the intersection of the curves in FIG. 3, it can be seen that there is another set of intersections in addition to the position where the two targets actually exist. This another set of intersection positions is a positioning result when the positioning processing is performed by mistake in the combination of the received signals, and is the position of the virtual image caused by the combination problem.

  FIG. 4 shows a relationship diagram between the target position and the angle measurement value in the configuration of FIG. 2 as in the case of FIG. In FIG. 4, two solid lines starting from the observation point 2A represent the angle measurement value direction of the angle measurement sensor AS at the observation point 2A. Similarly, two dotted lines starting from the observation point 3A represent the angle measurement direction of the angle measurement sensor AS at the observation point 3A. The intersection of these straight lines represents the estimation result of the target position vector, similarly to the intersection of the isochronous curves. However, even in the case of the intersection of the straight lines in the angle measurement value direction, another set of virtual images exists in addition to the true target position due to the existence of two targets.

  Comparing Fig. 3 corresponding to positioning based on the reception time and Fig. 4 corresponding to positioning based on angle measurement values, both have the same intersection at the true target position, and both are another set. It can be seen that there is an intersection corresponding to the virtual image. However, paying attention to the position of the virtual image, the position of the virtual image is different between FIG. 3 and FIG. Using this point, if all target position vector candidates at the reception time are compared with all target position vector candidates at the angle measurement value, and the closest target position vector candidate is regarded as a true positioning result, a plurality of Know the location of each target. If the positions of a plurality of targets are known, the combination of reception times can be found from FIG. 3, and since the Doppler frequencies corresponding to the reception times are known from FIG. 17, the combination of Doppler frequencies can also be known and the target velocity vector can be estimated similarly.

  FIG. 5 is a functional block diagram showing the flow of processing by an example of the positioning / speed measurement computing unit C of the radar apparatus according to Embodiment 1 of the present invention. In FIG. 5, the angle measurement values observed by the angle sensor AS at each observation point are sent to the target position vector candidate calculation unit 5. The target position vector candidate calculation unit 5 calculates target position vector candidates corresponding to all combinations of angle measurement values. For each of these target position vector candidates, the reception time candidate calculation unit 6 calculates a calculated value of the reception time using the above-described equation (1) or equation (2). The calculated reception time calculation value is sent to the reception time calculation value / observation value comparison unit 7. The received time calculated value / observed value comparing unit 7 creates the following evaluation function for comparing the calculated received time with the actual observed value obtained by the time / frequency sensor TDS at each observation point. .

Expressions (5) to (8) are evaluation expressions for combining received signals at the observation point 2A. _pTK represents the kth target position vector candidate, and the odd-numbered and the next even-numbered target position vector candidates are combined. Expression (5) represents an evaluation function f (p _T1 , p _T2 ) when a combination of the target position vector p _T1 and the target position vector p _T2 is evaluated as a target position vector candidate. (Swang dash) τ _n (p _T1 ) is the calculated value of the reception time at observation point n calculated from p _T1 , and τ _{n, m} is the mth observation value of the reception time at observation point n. is there. This evaluation function f (p _T1 , p _T2 ) is obtained when p _T1 and p _{T2 correspond} to the reception time observation values τ _{2A, 1} , τ _{2A, 2} in an ideal situation without an observation error. The value is 0. Equation (6) is obtained by reversing the combination of the target position vector p _T1 and the target position vector p _T2, the reception time observed value τ _{2A, 1,} the tau _{2A, 2} of correspondence. Expressions (7) and (8) are the same evaluation expressions as Expressions (5) and (6) for the combination of p _T3 and p _T4 .

Thus, performing the derivation of the reception time calculation value, the observed value comparison unit 7, for all combinations of p _Tk evaluation function _{f (p Tk, p T (} k + 1)). The received signal combination determination unit 8 searches for a combination of target position vectors having the minimum value from the evaluation function of each combination (equations (5) to (8) in the case of two targets), and each target position A combination of received signals is determined from the observation value of the reception time corresponding to the vector. The positioning / speed measurement calculation unit 9 uses the combination of the reception time of each time / frequency sensor TDS determined by the reception signal combination determination unit 8 and the observed value of the Doppler frequency to calculate the positioning / speed measurement calculation of each target using equation (1). Perform by ~ (4). Thereby, the position vector / velocity vector of each of the plurality of targets is estimated.

  In the processing flow of FIG. 5, the target position vector candidate obtained from the reception time is not compared with the target position vector candidate obtained from the angle measurement value, but is received from the target position vector candidate obtained from the angle measurement value. The process is to calculate the time and compare the calculated value and the observed value. This is because, when the target position vector is derived from the angle measurement value, the linear simultaneous equations are solved, whereas when the target position vector is derived from the reception time, the nonlinear simultaneous equations must be solved. By using the processing flow of FIG. 5, there is an aim of avoiding the nonlinear simultaneous equations as much as possible and reducing the calculation load.

  However, as shown in FIG. 6, target position vector candidate calculation units 5 and 10 derive target position vector candidates from both the angle measurement value and the reception time, and target position vector candidate comparison unit 7A compares these candidates. It is also possible to solve the combination problem. In the processing flow of FIG. 6, the target position vector candidate calculation unit 10 calculates the target position vector candidate from the reception time information observed by each time / frequency sensor TDS. Similar to the case of FIG. 5, the target position vector candidate calculation unit 5 calculates the target position vector candidate also from the angle measurement value. The target position vector candidates calculated from the reception time and the angle measurement value are sent to the target position vector candidate comparison unit 7A, and a true target position combination is selected from the difference in virtual image positions. Thereby, the combination of the received signals is determined, and the position vector / velocity vector of each of the plurality of targets can be estimated.

  Further, the angle measurement value and the reception time in FIG. 5 are interchanged, a target position vector candidate is calculated from the reception time, an angle measurement value is calculated from the target position vector candidate, and the calculated value of the angle measurement value is compared with the observation value. Therefore, it is possible to solve the combination problem. The processing flow in that case is shown in FIG. In the processing flow of FIG. 7, the target position vector candidate calculation unit 10 calculates the target position vector candidate from the reception time information observed by each sensor as in FIG. 6. In the case of FIG. 7, a calculated value of the measured angle value is calculated from the target position vector candidate by the measured angle value candidate calculating unit 11, and the measured value of the measured angle value is calculated by the measured angle value calculated value / observed value comparing unit 7B. And the received signal combination is determined. 6 and FIG. 7 is different in comparison, but the point of eliminating virtual images at the time of multiple targets using information on the target position vector candidates is the flow of processing shown in FIG. And are within the scope of the present invention.

  In the above description, an example in which the target number is 2 has been used. Of course, similar processing is possible when the target number is 3 or more. In this case, the number of received signals increases according to the target number, and the number of combinations of received signals increases. As a result, the number of combinations of calculated values and observation values that are the targets of creating evaluation functions will increase, but the process of determining the combination of received signals by finding the smallest value from the evaluation functions of each combination. There is no change. From this, the position vector and velocity vector of each target can be similarly estimated even when the number of targets is three or more.

  As described above, in addition to the time / frequency sensor TDS for observing the reception time and the Doppler frequency at each observation point, the angle measurement sensor AS for observing the target direction is provided, and the target based on the angle measurement value of the angle measurement sensor AS. In the first embodiment of the present invention, the position vector information and the target position vector information according to the reception time are compared to solve the received signal combination problem and perform the positioning / speed measurement processing.

Embodiment 2. FIG.
The schematic configuration and arrangement of a radar apparatus according to Embodiment 2 of the present invention are the same as those shown in FIGS. However, in the second embodiment, the observation rate of the angle measurement sensor AS at each observation point is higher than that of the time / frequency sensor TDS for acquiring the reception time / Doppler frequency. An example is shown in FIG. 8A shows the observation timing of the time / frequency sensor TDS, FIG. 8B shows the observation timing of the angle sensor AS, the horizontal axis represents time, and each impulse represents the observation timing of each sensor. In the case of the example of FIG. 8, the angle measurement sensor AS performs two observations for one observation with the time / frequency sensor TDS. In the second embodiment of the present invention, focusing on this point, in addition to the comparison between the target position vector candidate in the time / frequency sensor TDS in the first embodiment and the target position vector candidate in the angle measurement sensor AS, The speed vector candidates derived by the sensor are also compared to determine a combination of received signals.

  FIG. 9 is a functional block diagram showing the flow of processing by an example in the positioning / speed measurement computing unit C of the radar apparatus according to Embodiment 2 of the present invention. FIG. 9 is based on the processing of FIG. 5, but unlike FIG. 5, angle measurement values exist for a plurality of time samples based on the observation timing of FIG. 8. The target position vector candidate calculation unit 5A performs positioning for these multiple time samples, and derives target position vector candidates for a plurality of time timings. The Doppler frequency candidate calculation unit 12 calculates a velocity vector for each target position candidate from the target position vector candidates at the plurality of time timings. This calculation may be based on a difference assuming constant velocity linear motion. Further, the Doppler frequency at each time / frequency sensor TDS corresponding to the value is calculated from each calculated velocity vector. The Doppler frequency calculation value corresponding to each target position vector candidate calculated by the Doppler frequency candidate calculation unit 12 is sent to the calculated value / observation value comparison unit 7C as a target position vector at a plurality of time timings of the target position vector candidate calculation unit 5A. The candidate is sent together with the reception time calculation value calculated by the reception time candidate calculation unit 6.

  In the calculated value / observed value comparison unit 7C, the evaluation function for comparing the calculated value calculated by the angle measurement value and the observed value from the time / frequency sensor TDS is the same as the processing flow of FIG. 5 of the first embodiment. Is created. However, in the second embodiment, since the calculated value and the observed value are compared not only for the reception time but also for the Doppler frequency, the evaluation function at the time of the two targets is as follows.

Expressions (9) to (12) are evaluation expressions for combining received signals at the observation point 2A. (Swang dash) f _n (p _Tk ) is a calculated value of the Doppler frequency at the observation point n calculated from the target position vector candidates of a plurality of time samples corresponding to the target position vector candidate p _Tk , and f _{n and m} are This is the m-th observed value of the Doppler frequency at the observation point n. Further, a is an arbitrary constant for compensating for the influence of the difference in the dimensions of the reception time and the Doppler frequency and the difference in observation accuracy. In Calculated and observation value comparison unit 7C, performs derivation of evaluation for all combinations of _{p Tk} function _{f '(p Tk, p T} (k + 1)). Similarly to the first embodiment, the reception signal combination determination unit 8 searches for a combination of target position vectors that minimizes the value of the evaluation function, and determines a combination of reception signals corresponding to each target position vector. Thereafter, the positioning / speed measurement calculation is performed by the combination of the received signals determined by the positioning / speed measurement calculation unit 9, and the target position vector / speed vector of each of the plurality of targets is estimated.

  In the processing flow of FIG. 9, Doppler frequencies are calculated from target velocity vector candidates obtained from angle measurement values of a plurality of time samples, and those calculated values are compared with observation values of the time / frequency sensor TDS. However, in the calculated value / observation value comparison unit 7C, the received signal is compared by comparing the target velocity vector obtained from the angle measurement values of a plurality of time samples with the target velocity vector obtained from the Doppler frequency observed by the time / frequency sensor TDS. The combination may be determined. In this case, the evaluation function calculates a square difference between the target velocity vector candidate based on the angle measurement value and the target velocity vector candidate based on the Doppler frequency.

  In this way, by comparing not only the information of the target position vector based on the angle measurement value and the information of the target position vector based on the reception time but also the speed vector information, the received signal combination problem can be solved, In the second embodiment of the present invention, positioning / speed measurement processing is performed on each of them.

Embodiment 3 FIG.
In the third embodiment of the present invention, when a false alarm occurs in the observation value of each sensor, positioning / speed measurement processing is performed for a plurality of targets in the same manner as in the first and second embodiments while dealing with the false alarm. Is. A false alarm is a phenomenon in which noise is mistaken as a target reflected wave when the intensity of the target reflected wave is low or the intensity of noise is high even though there is no received signal due to the target reflected wave. . For this reason, the time / frequency TDS observes the reception time / Doppler frequency separately from the one corresponding to the target reflected wave, and the angle measurement sensor AS observes the angle measurement value separately from the one corresponding to the target. Resulting in. The schematic configuration and arrangement of a radar apparatus according to Embodiment 3 of the present invention are the same as those shown in FIGS.

  FIG. 10 shows the relationship between the reception time at the time of a false alarm and the target position, and FIG. 11 shows the relationship between the angle measurement value at the time of a false alarm and the target position. 10 shows a case where one false alarm is generated in the received signals at the observation points 2A and 3A in FIG. 3, and FIG. 11 shows the angle measurement values at the observation points 2A and 3A in FIG. Each case where one false alarm is generated is shown.

  10 and 11, in the same manner as in the first and second embodiments, the target position vector candidate based on the reception time and the target speed vector based on the angle measurement value, or the target speed vector based on the Doppler frequency and the angle measurement value are used. Consider a combination of received signals by comparison of target velocity vectors. At this time, unlike the case where no false alarm exists, there is a problem that the actual target number is not known. In the state of FIGS. 10 and 11, the actual target number is 2, but the intersection of false alarms indicated by x in the figure is regarded as a target position vector, and the target number is assumed to be 3 to solve the problem. Is also possible. Of course, it is possible to solve by considering the target number as 2, or as 1. Therefore, in the third embodiment of the present invention, the combination of received signals is solved as before, and simultaneously the number of targets is estimated, and finally the positioning / speed measurement processing is performed for each target.

  In the case of FIG. 10 and FIG. 11, when considering the processing in the first and second embodiments so far, if the target number is assumed to be 3, the true target position vector × 2 + the target position due to the false alarm A combination of vectors is estimated as a positioning result. When the target number is assumed to be 2, a true target position vector × 2 is estimated as a positioning result, and when the target number is assumed to be 1, either of the true target position vectors is estimated as a positioning result. Consider an evaluation function based on the square difference between the observed value, calculated value, and target position vector candidates. Assuming that the target numbers are 2 and 1, the value of the evaluation function is 0 in a noiseless environment. However, when the target number is assumed to be 3, which is larger than the true target number, the term corresponding to the false alarm of the evaluation function is based on the difference in the target position vector due to the false alarm indicated by x in FIG. 10 and FIG. It will have a large value. That is, when the assumed target number is larger than the actual target number, the value of the evaluation function is not zero. Since there is actually an observation error, the result is as shown in FIG. In FIG. 12, the horizontal axis represents the assumed target number, and the vertical axis represents the minimum value of the evaluation function at each assumed target number.

  Thus, when the assumed target number is larger than the actual number, the value of the evaluation function suddenly increases. Using this point, set an arbitrary threshold value that takes observation error into consideration, and search for the target number with the maximum target number among the target numbers whose evaluation function is lower than that value. But you can determine the target number. This is the concept of the third embodiment.

  FIG. 13 is a functional block diagram showing the flow of processing by an example of the positioning / speed measurement computing unit C of the radar apparatus according to Embodiment 3 of the present invention. FIG. 13 corresponds to FIG. 5 of the processing flow of the first embodiment. In FIG. 13, a target position vector candidate is calculated by the target position vector candidate calculation unit 5 using all angle measurement values including false alarms. From these target position vector candidates, the reception time candidate calculation unit 6 calculates reception time candidates and sends them to the reception time calculation value / observation value comparison unit 7D. In the reception time calculation value / observation value comparison unit 7D, not only combinations of reception times but also evaluation functions are calculated for all combinations in which the assumed target number is changed within an arbitrary range. The target number / received signal combination determination unit 8A determines the combination of the target number and the received signal by searching for the minimum value of the evaluation function having the maximum target number and not more than the threshold value. Thereafter, the target position vector and speed vector of each target are estimated by the positioning / speed measurement calculation unit 9.

  FIG. 13 corresponds to the processing flow of FIG. 5 of the first embodiment. However, as shown in FIG. 6 and FIG. 7 of the first embodiment, the comparison between the target position vectors and the calculated value of the angle measurement value By comparing the observed values, it is also possible to perform positioning / speed measurement processing while dealing with false alarms.

  In this way, while searching for the minimum value of the evaluation function that takes a value below an arbitrary threshold while changing the assumed target number, positioning is performed for each of the multiple targets while determining the target number even under false alarm environments. The speed measurement process is performed in the third embodiment of the present invention.

Embodiment 4 FIG.
In the first to third embodiments so far, the positioning / speed measurement result using the reception time of the time / frequency sensor TDS and the Doppler frequency is used as the final estimation result. That is, in the positioning / speed measurement processing by the time / frequency sensor TDS, the information of the angle sensor AS is used to deal with a plurality of targets. In the fourth embodiment of the present invention, contrary to the first to third embodiments, the reception time of the time / frequency sensor TDS is used to deal with a plurality of targets in the positioning process using the angle measurement values by the plurality of angle measurement sensors AS. Consider using information. The first difference from the first to third embodiments is that the final positioning result is not based on the reception time information but based on the angle measurement value.

  FIG. 14 is a functional block diagram showing the flow of processing in the positioning / speed measurement computing unit C of the radar apparatus according to Embodiment 4 of the present invention. In FIG. 14, the target position vector candidate calculation unit 5 calculates the target position vector candidate including the virtual image by linking the angle measurement values of the angle measurement sensor as before. From these target position vector candidates, a reception time candidate calculation unit 6 calculates a reception time calculation value, and a reception time calculation value / observation value comparison unit 7 calculates an evaluation function for comparison with the reception time observation value. The From the evaluation function, the target position vector virtual image removing unit 13 extracts a true target position vector from the target position vector candidates.

  In FIG. 14, the calculated value of the reception time is compared with the observed value, but in the fourth embodiment, false alarms are similarly obtained by comparing the target position vectors with each other or by comparing the calculated value of the angle measurement value and the observed value. Positioning / speed measurement processing may be performed while coping with the above.

  That is, when there are multiple targets, the reception time calculation value at each reception unit calculated from the target position vector candidate obtained from the angle measurement value observed at each reception unit, and the reception observed at each reception unit By comparing the time observation values, a combination of angle measurement values between the receiving units is determined, and a position vector of each of the plurality of targets is estimated.

  Alternatively, when there are a plurality of targets, a target position vector candidate obtained from an angle measurement value observed at each reception unit and a target position vector candidate obtained from a reception time observation value observed at each reception unit point By comparing, the combination of angle measurement values between the respective receiving units is determined, and the position vector of each of the plurality of targets is estimated.

  Alternatively, when there are a plurality of targets, the angle measurement value observed at each reception unit is compared with the angle measurement value calculated from the target position vector candidate obtained from the reception time observation value observed at each reception unit. Thus, a combination of angle measurement values between the respective receiving units is determined, and the position vector of each of the plurality of targets is estimated.

  As described above, the target position vector is obtained by using the reception time information of the time / frequency sensor TDS when performing positioning of a plurality of targets from the angle measurement values of the plurality of angle measurement sensors based on the same concept as in the first to third embodiments. The virtual image is removed in the fourth embodiment of the present invention.

  In each of the above embodiments, the transmission unit may be configured integrally with any of the plurality of reception units.

  Further, the present invention is not limited to the above-described embodiments, and it goes without saying that all possible combinations thereof are included.

  5, 5A target position vector candidate calculation unit, 6 reception time candidate calculation unit, 7 reception time calculated value / observation value comparison unit, 7A target position vector candidate comparison unit, 7B angle measurement value calculation value / observation value comparison unit, 7C calculation Value / observation value comparison unit, 7D reception time calculation value / observation value comparison unit, 8 reception signal combination determination unit, 8A target number / reception signal combination determination unit, 9 positioning / speed measurement calculation unit, 10 target position vector candidate calculation unit, DESCRIPTION OF SYMBOLS 11 Angle measurement value candidate calculation part, 12 Doppler frequency candidate calculation part, 13 Target position vector virtual image removal part, 100 transmission part, 200,300 reception part, AN transmission antenna, AS angle measurement sensor, C positioning / speed measurement calculation part, TDS Time / Doppler frequency sensor (time / frequency sensor).

Claims (14)

A transmitter that emits radio waves;
The time and Doppler frequency sensors for observing the reception time and the Doppler frequency for each target are received at the different observation points, respectively, and the reflected radio waves from the plurality of targets of the radiated radio wave of the transmission unit are received. A plurality of receiving units each having an angle measuring sensor for observation;
A positioning / speed measurement computing unit including first means for estimating the position and velocity vectors of the target from the reception time, Doppler frequency and angle measurement value observed by each of the receiving units, ,
Equipped with a,
When the first means of the positioning / speed measurement calculation unit has a plurality of targets, the reception time calculation value at each reception unit calculated from the target position vector candidate obtained from the angle measurement value observed at each reception unit And the received time observation value observed at each receiving unit to determine the combination of the received time observed value and the Doppler frequency observed value between the receiving units, and the position vector and velocity vector of each of the multiple targets are determined. presume,
Radar apparatus characterized by the above. A transmitter that emits radio waves;
The time and Doppler frequency sensors for observing the reception time and the Doppler frequency for each target are received at the different observation points, respectively, and the reflected radio waves from the plurality of targets of the radiated radio wave of the transmission unit are received. A plurality of receiving units each having an angle measuring sensor for observation;
A positioning / speed measurement computing unit including first means for estimating the position and velocity vectors of the target from the reception time, Doppler frequency and angle measurement value observed by each of the receiving units, ,
Equipped with a,
When the first means of the positioning / speed measurement calculation unit has a plurality of targets, the target position vector candidate obtained from the measured angle value observed at each receiving unit and the reception time observation observed at each receiving unit By comparing the target position vector candidates obtained from the values, the combination of the reception time observation value and the Doppler frequency observation value between the respective receivers is determined, and the position vector and velocity vector of each of the multiple targets are estimated.
Radar apparatus characterized by the above. A transmitter that emits radio waves;
The time and Doppler frequency sensors for observing the reception time and the Doppler frequency for each target are received at the different observation points, respectively, and the reflected radio waves from the plurality of targets of the radiated radio wave of the transmission unit are received. A plurality of receiving units each having an angle measuring sensor for observation;
A positioning / speed measurement computing unit including first means for estimating the position and velocity vectors of the target from the reception time, Doppler frequency and angle measurement value observed by each of the receiving units, ,
Equipped with a,
When the first means of the positioning / speed measurement calculation unit has a plurality of targets, the target position vector obtained from the angle measurement value observed at each reception unit and the reception time observation value observed at each reception unit By comparing the calculated value of the angle measurement value at each receiving unit calculated from the candidates, the combination of the reception time observation value and the Doppler frequency observation value between each receiving unit is determined, and the position vector of each of the multiple targets is determined. Estimate the velocity vector,
Radar apparatus characterized by the above. The positioning / speed measurement computing unit includes a second means for estimating a target velocity vector from a plurality of samples of angle values of each receiving unit;
The first means not only compares the target position vector or the reception time or angle value information but also calculates the Doppler frequency value at each receiver calculated from the velocity vector obtained from the angle value of each receiver. By comparing the Doppler frequency observation values observed at each receiver, the combination of the reception time observation value and Doppler frequency observation value between each receiver is determined, and the position vector and velocity vector of each of the multiple targets are determined. The radar device according to claim 1 , wherein the radar device is estimated. The positioning / speed measurement computing unit includes a second means for estimating a target velocity vector from a plurality of samples of angle values of each receiving unit;
The first means calculates not only the target position vector or the reception time or angle value information but also the velocity vector obtained from the angle value of each receiver and the Doppler frequency observed at each receiver. velocity vector also be compared, from claim 1 to determine a combination of the received time observations and Doppler frequency observed values among the receiving unit, and estimates the position and velocity vectors of a plurality target 4. The radar device according to any one of up to 3 . The positioning / speed measurement calculation unit determines the target number by evaluating the combination while changing the assumed target number when determining the combination of the reception time observation value and the Doppler frequency observation value between each reception unit. The radar apparatus according to claim 1 , wherein a position vector and a velocity vector are estimated. A transmitter that emits radio waves;
The time and Doppler frequency sensors for observing the reception time and the Doppler frequency for each target are received at the different observation points, respectively, and the reflected radio waves from the plurality of targets of the radiated radio wave of the transmission unit are received. A plurality of receiving units each having an angle measuring sensor for observation;
A positioning / speed measurement computing unit including first means for estimating the position and velocity vectors of the target from the reception time, Doppler frequency and angle measurement value observed by each of the receiving units, ,
Equipped with a,
When the first means of the positioning / speed measurement calculation unit has a plurality of targets, the reception time calculation value at each reception unit calculated from the target position vector candidate obtained from the angle measurement value observed at each reception unit And, by comparing the reception time observation values observed at each receiver, determine the combination of angle measurement values between each receiver, and estimate the position vector of each of the multiple targets.
Radar apparatus characterized by the above. A transmitter that emits radio waves;
The time and Doppler frequency sensors for observing the reception time and the Doppler frequency for each target are received at the different observation points, respectively, and the reflected radio waves from the plurality of targets of the radiated radio wave of the transmission unit are received. A plurality of receiving units each having an angle measuring sensor for observation;
A positioning / speed measurement computing unit including first means for estimating the position and velocity vectors of the target from the reception time, Doppler frequency and angle measurement value observed by each of the receiving units, ,
Equipped with a,
When the first means of the positioning / speed measurement computing unit has a plurality of targets, the target position vector candidates obtained from the measured angle values observed at each receiving unit and the reception times observed at each receiving unit point By comparing the target position vector candidates obtained from the observed values, the combination of angle measurement values between the respective receivers is determined, and the position vector of each of the multiple targets is estimated.
Radar apparatus characterized by the above. A transmitter that emits radio waves;
The time and Doppler frequency sensors for observing the reception time and the Doppler frequency for each target are received at the different observation points, respectively, and the reflected radio waves from the plurality of targets of the radiated radio wave of the transmission unit are received. A plurality of receiving units each having an angle measuring sensor for observation;
A positioning / speed measurement computing unit including first means for estimating the position and velocity vectors of the target from the reception time, Doppler frequency and angle measurement value observed by each of the receiving units, ,
Equipped with a,
When the first means of the positioning / speed measurement calculation unit has a plurality of targets, the target position vector obtained from the angle measurement value observed at each reception unit and the reception time observation value observed at each reception unit By comparing the measured angle values calculated from the candidates, determine the combination of measured angle values between each receiver, and estimate the position vector of each of the multiple targets.
Radar apparatus characterized by the above. Claims, characterized in that when the combination determining the measured angle values between the respective receiving unit, estimates the position vector of each of the plurality target determines the target number by the evaluation of combinations while changing the number of assumed target The radar apparatus according to any one of 7 to 9 . The radar apparatus according to claim 1, wherein the transmission unit is provided integrally with any one of the reception units. The radar apparatus according to any one of claims 1 to 11, further comprising two or more receiving units, and obtaining a two-dimensional position and velocity of each target. The radar apparatus according to any one of claims 1 to 11, further comprising three or more receiving units, and obtaining a three-dimensional position and velocity of each target. The radar device according to any one of claims 1 to 13 , wherein an IR sensor is used as the angle measuring sensor.

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