Radar target tracking device and radar target tracking program

Abstract

To reduce the possibility of erroneously linking clutter to a target of interest, and to reduce the possibility of interrupting tracking processing of the target of interest without narrowing the prediction gate of the target of interest, even when the density of clutter due to waves, clouds, or the like is high, in tracking a target such as a ship or aircraft using a radar.SOLUTION: The present disclosure relates to a radar target tracking device 2 including an inter-scan correlation unit 14 that calculates, for each of targets inside a prediction gate of a target of interest in each radar scan, an inter-scan change rate from the predicted Doppler velocity and / or received power of the target of interest in a previous radar scan to the observed Doppler velocity and / or received power of each target in each radar scan, and a target tracking unit 15 that links, among the targets inside the prediction gate of the target of interest in each radar scan, a target with the smallest inter-scan change rate to the target of interest.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to techniques for tracking targets using radar. [Background technology]

[0002] A technology for tracking a target using a radar is disclosed in Patent Document 1 and the like. In Patent Document 1, in each radar scan, detection points are clustered, and the position, observed Doppler velocity, and reception strength of the radar's transmitting and receiving device of each target are detected. Then, in each radar scan, the position and Doppler velocity of each target are predicted in preparation for the next radar scan, and a prediction gate for each target is set with the predicted position of each target at the center. Furthermore, in each radar scan, among the targets inside the prediction gate of the target of interest, the target closest to the predicted position of the target of interest is linked to the target of interest.

[0003] However, in each radar scan, there may be multiple targets that are the same distance from the predicted position of the target of interest and have the same reception strength of the radar transmitter / receiver. Therefore, in each radar scan, the target that has the closest observed Doppler velocity to the predicted Doppler velocity of the target of interest is linked to the target of interest. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2002-341025 A Summary of the Invention [Problem to be solved by the invention]

[0005] A specific example of a radar target tracking process according to the prior art is shown in FIG. 1. In FIG. 1, the detected position of a target of interest Tv in the previous radar scan is P v and in the latest radar scan, the predicted position of the target of interest Tv is P v', and a prediction gate G of the target Tv is set. Then, in the latest radar scan, within the prediction gate G of the target Tv, the detection positions of the targets Ta, Tb, Tc, and Td are P a , P b , P c , P d (target Tc does not exist in the right column), and targets Te, Tf, and Tg exist outside the prediction gate G of the target of interest Tv.

[0006] In FIG. 1, the target of interest Tv and target Tc are ships or aircraft, etc. (in the right column, target Tc cannot be observed by the radar for some reason (factors due to the target itself being submerged, accidental factors due to the positional relationship and motion state between the target itself and another target, or some factor in the radar signal processing, etc.)), and targets Ta, Tb, Td, Te, Tf, and Tg are clutter due to waves, clouds, etc. Then, when the density of clutter is high, target Tb, which is clutter, will be detected from the predicted position P of the target of interest Tv. v ', there is a high possibility that the clutter target Tb will be erroneously linked to the target of interest Tv. In addition, there is a high possibility that the clutter target Tb will be erroneously tracked in the next or subsequent radar scans. On the other hand, when the prediction gate G of the target of interest Tv is narrow, there is a low possibility that the clutter target Tb will be erroneously linked to the target of interest Tv. However, when the predicted position P v If the detection position P of the target Tc is not predicted with high accuracy, c However, since the target of interest Tv is not present inside the prediction gate G, there is a high possibility that the tracking process of the target of interest Tv will be interrupted.

[0007] Therefore, in order to solve the above-mentioned problems, the present disclosure aims to reduce the possibility of erroneously linking clutter to a target of interest when using a radar to track a target such as a ship or aircraft, even when the density of clutter due to waves, clouds, etc. is high, and to reduce the possibility of interrupting the tracking process of the target of interest without narrowing the prediction gate of the target of interest. [Means for solving the problem]

[0008] In order to solve the above problem, attention is paid to the fact that the predicted and observed Doppler velocities and / or received power of each target do not change suddenly for each radar scan (for example, about several seconds). In other words, for each target inside the prediction gate of the target of interest, the scan-to-scan change rate from the predicted Doppler velocity and / or received power of the target of interest in the previous radar scan to the observed Doppler velocity and / or received power of each target in each radar scan is calculated. Then, among the targets inside the prediction gate of the target of interest, the target with the smallest scan-to-scan change rate is linked to the target of interest. Here, if each target is inside the prediction gate of the target of interest, it is treated equally regardless of the distance from the predicted position of the target of interest, and attention is paid to the scan-to-scan change rate of the predicted and observed Doppler velocities and / or received power.

[0009] Specifically, the present disclosure provides a radar target tracking device comprising: a target detection unit that performs clustering of detection points, detects the position of each target, and detects at least one of an observed Doppler velocity and a received power of each target in each radar scan; a target position prediction unit that predicts the position of each target in each radar scan in preparation for the next radar scan, predicts the Doppler velocity of each target as necessary, and sets a prediction gate for each target centered on the predicted position of each target; an inter-scan correlation unit that calculates, for each target inside a prediction gate of a target of interest in each radar scan, a scan-to-scan rate of change from at least one of a predicted Doppler velocity and a received power of the target of interest in the previous radar scan to at least one of an observed Doppler velocity and a received power of each target in each radar scan; and a target tracking unit that links, among the targets inside the prediction gate of the target of interest in each radar scan, a target with the smallest inter-scan rate of change to the target of interest.

[0010] According to this configuration, since attention is paid to the inter-scan rate of change of predicted / observed Doppler velocity and / or received power for each target within the prediction gate of the target of interest, such as a ship or aircraft, it is possible to reduce the possibility of erroneously linking clutter to the target of interest, even when the density of clutter due to waves, clouds, etc. is high. Furthermore, since each target within the prediction gate of the target of interest, such as a ship or aircraft, is treated equally regardless of the distance from the predicted position of the target of interest, it is possible to reduce the possibility of interrupting the tracking process of the target of interest without narrowing the prediction gate of the target of interest.

[0011] The present disclosure also relates to a radar target tracking device, characterized in that in each radar scan, for each target inside a prediction gate of the target of interest, the inter-scan correlation unit calculates the inter-scan change rate by adding a predicted Doppler velocity change rate from the predicted Doppler velocity of the target of interest in the previous radar scan to the observed Doppler velocity of each target in each radar scan and a received power change rate from the received power of the target of interest in the previous radar scan to the received power of each target in each radar scan, with a weighting according to the distance of the target of interest from the radar or a motion state of the target of interest.

[0012] According to this configuration, it is possible to set which of the inter-scan change rates of the predicted and observed Doppler velocities and received power of each target is to be given more importance than the other inter-scan change rates, depending on the distance of the target from the radar or the motion state of the target.

[0013] The present disclosure also relates to a radar target tracking device, characterized in that the inter-scan correlation unit (1) increases the weighting on the predicted Doppler velocity change rate compared to the weighting on the received power rate as the distance of the target of interest from the radar increases, and increases the weighting on the received power rate compared to the weighting on the predicted Doppler velocity change rate as the distance of the target of interest from the radar decreases, or (2) keeps the ratio between the weighting on the predicted Doppler velocity change rate and the weighting on the received power rate approximately constant regardless of the distance of the target of interest from the radar.

[0014] With this configuration, it is possible to set weights for the scan-to-scan change rates of the predicted and observed Doppler velocities and received power of each target, taking into consideration that the scan-to-scan change rates of the predicted and observed Doppler velocities of the target of interest are smaller / larger as the distance of the target of interest from the radar increases / decreases.On the other hand, it is also possible to make the ratio of weights for the scan-to-scan change rates of the predicted and observed Doppler velocities and received power of each target approximately constant, taking into consideration that the scan-to-scan change rates of the predicted and observed Doppler velocities of the target of interest are small regardless of the distance of the target of interest from the radar.

[0015] The present disclosure also relates to a radar target tracking device, characterized in that the inter-scan correlation unit (1) increases the weighting on the predicted Doppler velocity change rate compared to the weighting on the received power rate as the motion state of the target is a constant velocity state, and increases the weighting on the received power rate compared to the weighting on the predicted Doppler velocity change rate as the motion state of the target is a rapid acceleration / deceleration state, or (2) when the target position prediction unit predicts whether the motion state of the target of interest is a constant velocity state or a rapid acceleration / deceleration state based on multiple past radar scans, keeps the ratio between the weighting on the predicted Doppler velocity change rate and the weighting on the received power rate approximately constant regardless of the motion state of the target of interest.

[0016] According to this configuration, it is possible to set weights for the scan-to-scan change rates of the predicted and observed Doppler velocities and received power of each target, taking into consideration that the more the motion state of the target of interest is at a constant speed / rapid acceleration / deceleration state, the smaller / larger the scan-to-scan change rate of the predicted and observed Doppler velocities of the target of interest. On the other hand, when the motion state of the target of interest is predicted based on multiple past radar scans, it is also possible to make the weighting ratios for the scan-to-scan change rates of the predicted and observed Doppler velocities and received power of each target approximately constant, taking into consideration that the scan-to-scan change rate of the predicted and observed Doppler velocities of the target of interest is small regardless of the motion state of the target of interest.

[0017] The present disclosure also provides a radar target tracking program for causing a computer to execute each processing step executed by each processing unit included in the above-described radar target tracking device.

[0018] According to this configuration, it is possible to provide a program having the above-described effects.

[0019] The above disclosed inventions can be combined to the greatest extent possible. Effect of the Invention

[0020] In this way, when using a radar to track a target such as a ship or aircraft, the present disclosure can reduce the possibility of erroneously linking clutter to a target of interest, even when the density of clutter due to waves, clouds, etc. is high, and can also reduce the possibility of interrupting the tracking process of the target of interest without narrowing the prediction gate of the target of interest. [Brief description of the drawings]

[0021] [Figure 1] FIG. 1 is a diagram showing a specific example of radar target tracking processing according to the prior art; [Diagram 2] 1 is a diagram showing a configuration of a radar target tracking system according to the present disclosure. [Diagram 3] FIG. 4 is a diagram showing a procedure of a radar target tracking process according to the present disclosure. [Figure 4]1A to 1C are diagrams illustrating a specific example of a radar target tracking process according to the present disclosure. [Diagram 5] FIG. 13 illustrates weighting of predicted Doppler velocity and rate of change of received power according to the present disclosure. [Figure 6] FIG. 13 illustrates weighting of predicted Doppler velocity and rate of change of received power according to the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present disclosure will be described with reference to the accompanying drawings. The embodiments described below are examples of the present disclosure, and the present disclosure is not limited to the following embodiments.

[0023] (Overview of radar target tracking processing according to the present disclosure) The configuration of the radar target tracking system of the present disclosure is shown in Fig. 2. The procedure of the radar target tracking process of the present disclosure is shown in Fig. 3. The radar target tracking system R includes a radar transceiver 1, a radar target tracking device 2, and a radar display device 3. The radar transceiver 1 transmits and receives radar, the radar target tracking device 2 tracks a target T, and the radar display device 3 displays the target T.

[0024] The radar target tracking device 2 includes a target detection unit 11, a target memory unit 12, a target position prediction unit 13, an inter-scan correlation unit 14, and a target tracking unit 15. The radar target tracking device 2 can be realized by installing the radar target tracking program shown in Fig. 3 in a computer.

[0025] The target detection unit 11 performs clustering of the detection points in each radar scan and calculates the position P of each target. n , the observed Doppler velocity D оn and the received power W n (Step S1). Here, the target detection unit 11 clusters the detection points using DBSCAN (Density-Based Spatial Clustering of Applications with Noise) or the like. Then, the target detection unit 11 detects the center of gravity of each target or the average observed Doppler velocity Dоn Furthermore, the target detection unit 11 detects the received power W of each target based on the peak power of all the detection points of each target, the average power of all the detection points of each target, or the sum of the power of all the detection points of each target. n However, the target detection unit 11 detects the received power W of each target based on the power sum of all detection point powers of each target. n When detecting the position P of each target, it is desirable not to confuse a target having a large size and a small radar cross section, such as a wave, cloud, or rain, with a target having a small size and a large radar cross section, such as a ship or aircraft. n , the observed Doppler velocity D оn and the received power W n The information is stored.

[0026] The target position prediction unit 13 predicts the position P of each target in each radar scan in preparation for the next radar scan. n ' and Doppler velocity D pn and predict the predicted position P n A prediction gate for each target is set with the target position P' at the center (step S2). Here, the target position prediction unit 13 uses a Kalman filter or the like to predict the position P n Then, the target position prediction unit 13 predicts the predicted position P n The radius of the prediction gate of each target is not too wide or too narrow with respect to the target position P'. Furthermore, the target position prediction unit 13 estimates the position P n and the predicted position P of each target in the next radar scan. n ' and the predicted position P of each target as seen by the radar target tracking system R. n Based on the direction of ' and the radar scan interval, the Doppler velocity D of each target in the next radar scan is calculated. pn Predict.

[0027] A specific example of the radar target tracking process of the present disclosure is shown in Fig. 4. In Fig. 4, in the previous radar scan, the combination of (detection position, observed Doppler velocity, received power) of the target of interest Tv is (P v , D оv, W v ) and in the latest radar scan, the predicted position of the target of interest Tv is P v ', and the predicted Doppler velocity of the target Tv is D pv and a prediction gate G of the target Tv is set. In the latest radar scan, within the prediction gate G of the target Tv, the combination of (detection position, observed Doppler velocity, received power) of the targets Ta, Tb, Tc, and Td is as follows: a , D оa , W a ), (P b , D оb , W b ), (P c , D оc , W c ), (P d , D оd , W d ) (target Tc does not exist in the right column), and targets Te, Tf, and Tg exist outside the prediction gate G of the target of interest Tv.

[0028] In FIG. 4, the targets of interest Tv and Tc are ships or aircraft, etc. (in the right column, the target Tc cannot be observed by the radar for some reason (factors due to the target itself being submerged, accidental factors due to the positional relationship and motion state between the target itself and another target, or some factors in the radar signal processing, etc.)), and the targets Ta, Tb, Td, Te, Tf, Tg are clutter due to waves, clouds, etc. Here, the targets Ta, Tb, Td, Te, Tf, Tg have roughly the same speed, and the targets of interest Tv and Tc have different speeds. It is noted that the predicted and observed Doppler velocities and received power of the targets Ta, Tb, Tc, Td, Te, Tf, Tg do not change suddenly for each radar scan (for example, within a few seconds) even if each target is swaying due to waves or wind, changing direction, or suddenly accelerating or decelerating. In other words, if the targets Ta, Tb, Tc, and Td are inside the prediction gate G of the target of interest Tv, the predicted position P v We treat all satellites equally regardless of their distance from the target, and focus on the scan-to-scan rate of change in predicted and observed Doppler velocities and received power.

[0029] In each radar scan, for each target within the prediction gate of the target of interest (step S3, YES), the inter-scan correlation unit 14 calculates the predicted Doppler velocity D of the target of interest in the previous radar scan. pv and the received power W v From the Doppler velocity D of each target in each radar scan, оn and the received power W n Scan-to-scan change rate X n =α|D pv -D оn |+β|W v -W n Here, the inter-scan correlation unit 14 calculates the predicted Doppler velocity change rate |D pv -D оn | and the rate of change of received power |W v -W n | and are added with weights α and β according to the distance of the target of interest from the radar or the motion state of the target of interest. On the other hand, in each radar scan, for each target outside the prediction gate of the target of interest (step S3, NO), the inter-scan correlation unit 14 does not link the target to the target of interest (step S8).

[0030] In FIG. 4, the scan-to-scan change rates X a =α|D pv -D оa |+β|W v -W a |, X b =α|D pv -D оb |+β|W v -W b |, X c =α|D pv -D оc |+β|W v -W c |, X d =α|D pv -D оd |+β|W v -W dis calculated (target Tc does not exist in the right column). On the other hand, targets Te, Tf, and Tg outside the prediction gate G of the target of interest Tv are not linked to the target of interest Tv.

[0031] The target tracking unit 15 calculates the inter-scan change rate X of each target within the prediction gate of the target of interest in each radar scan. n is equal to or smaller than the predetermined threshold (step S5, YES), and the scan-to-scan change rate X n The target with the smallest change rate X n The target tracking unit 15 does not associate a target having a scan-to-scan change rate X n Although the scan-to-scan change rate X n If the target is not the smallest (step S6, NO), it is not associated with the target of interest (step S8). n , the observed Doppler velocity D оn and the received power W n The information is stored.

[0032] In the left column of Figure 4, the scan-to-scan change rate X c The smallest target Tc that is equal to or smaller than the predetermined threshold is linked to the target of interest Tv. a , X b , X d For targets Ta, Tb, and Td whose predicted position P v Even if the target Tb is closest to the target T, the scan-to-scan change rate X b Based on the size of the target, it is not linked to the target of interest Tv. In addition, when tracking a target of interest other than the target of interest Tv, the target Tc is excluded as a tracking candidate.

[0033] In the right column of Figure 4, the scan-to-scan change rate X n is equal to or smaller than the predetermined threshold, and the smallest target does not exist, so it is determined that the target of interest Tv has been lost. On the other hand, the scan-to-scan change rate X a , X b , X d For targets Ta, Tb, and Td whose predicted position P v Even if the target Tb is closest to the target T, the scan-to-scan change rate X b Based on the size of the target, it is not linked to the target of interest Tv.

[0034] In this way, since attention is paid to the rate of change between predicted and observed Doppler velocities and received power between scans for each target within the prediction gate of a target of interest such as a ship or aircraft, it is possible to reduce the possibility of erroneously linking clutter to the target of interest even when the density of clutter due to waves, clouds, etc. is high. Furthermore, since each target within the prediction gate of a target of interest such as a ship or aircraft is treated equally regardless of its distance from the predicted position of the target of interest, it is possible to reduce the possibility of interrupting the tracking process of the target of interest without narrowing the prediction gate of the target of interest.

[0035] (Weighting for predicted Doppler velocity and rate of change of received power according to the present disclosure) The weighting of the predicted Doppler velocity and the rate of change of the received power according to the present disclosure is shown in Figs. 5 and 6. The inter-scan correlation unit 14 calculates the predicted Doppler velocity change rate |D pv -D оn | and the rate of change of received power |W v -W n | and are added with weights α and β according to the distance from the radar of the target of interest or the motion state of the target of interest (step S4). Specific examples of the weights α and β are shown in Figs.

[0036] In the left column of Fig. 5, the target of interest Tv in the previous radar scan crosses the radar target tracking system R at a long distance from the radar target tracking system R as it moves to the detection position of the target Tn in the latest radar scan. The inter-scan correlation unit 14 calculates the predicted Doppler velocity change rate |D pv -D оn The weighting α for the received power change rate |W v -W n The weighting factor β for | is set to be larger than the weighting factor β for |. The scan-to-scan change rate X of the target Tn being tracked n should be minimized, but the farther the target Tv is from the radar, the greater the observed Doppler velocity change rate |D оv -D оn Since | is small, the predicted Doppler velocity rate of change of target Tn |D pv -D оn The reason is that the received power change rate |W v -W n The weighting β for | may be set to 0.

[0037] In the right column of Fig. 5, when the target of interest Tv in the previous radar scan moves to the detection position of the target Tn in the latest radar scan, it crosses the radar target tracking system R at a short distance from the radar target tracking system R. The inter-scan correlation unit 14 calculates that the closer the distance of the target of interest Tv from the radar, the greater the change rate of the received power |W v -W n The weighting β for the predicted Doppler velocity change rate |D pv -D оn The weighting factor α for | is set to be larger than the weighting factor α for |. The scan-to-scan change rate X of the target Tn being tracked n should be minimized, but the closer the target Tv is to the radar, the smaller the observed Doppler velocity change rate |D оv -D оn Because | is large, the predicted Doppler velocity rate of change of target Tn |D pv -D оn The predicted Doppler velocity change rate |D pv -Dоn The weighting α for | may be set to 0.

[0038] On the other hand, in the left and right columns of FIG. 5, the inter-scan correlation unit 14 does not depend on the distance of the target of interest Tv from the radar, but instead predicts the Doppler velocity change rate |D pv -D оn Weighting α for | and the received power change rate |W v -W n The ratio between the weighting β for | and |D pv -D оn This is because | is considered to be small. Note that the ratio between the weights α and β may be changed slightly or may be changed at all between the left and right columns of FIG.

[0039] In the left column of FIG. 6, the target Tv of interest in the previous radar scan approaches the radar target tracking system R at a constant speed as it moves to the detection position of the target Tn in the latest radar scan. The inter-scan correlation unit 14 calculates the predicted Doppler velocity change rate |D pv -D оn The weighting α for the received power change rate |W v -W n The weighting factor β for | is set to be larger than the weighting factor β for |. The scan-to-scan change rate X of the target Tn being tracked n should be minimized, but the more constant the motion state of the target Tv, the smaller the observed Doppler velocity change rate |D оv -D оn Since | is small, the predicted Doppler velocity rate of change of target Tn |D pv -D оn The reason is that the received power change rate |W v -W n The weighting β for | may be set to 0.

[0040] In the right column of FIG. 6, the target of interest Tv in the previous radar scan approaches the radar target tracking system R in a rapid acceleration / deceleration state as it moves to the detection position of the target Tn in the latest radar scan. The inter-scan correlation unit 14 calculates the received power change rate |W v -W n The weighting β for the predicted Doppler velocity change rate |D pv -D оn The weighting factor α for | is set to be larger than the weighting factor α for |. The scan-to-scan change rate X of the target Tn being tracked n should be minimized, but the more rapid the acceleration / deceleration of the target Tv, the smaller the observed Doppler velocity change rate |D оv -D оn Because | is large, the predicted Doppler velocity rate of change of target Tn |D pv -D оn The predicted Doppler velocity change rate |D pv -D оn The weighting α for | may be set to 0.

[0041] On the other hand, in the left and right columns of FIG. 6, the scan-to-scan correlator 14 does not depend on the motion state of the target of interest Tv, and instead calculates the predicted Doppler velocity change rate |D pv -D оn Weighting α for | and the received power change rate |W v -W n The ratio between the weighting β for | and |D pv -D оn This is because | is considered to be small. However, it is desirable that the target position prediction unit 13 predicts whether the motion state of the target of interest Tv is a constant speed state or a rapid acceleration / deceleration state based on not only the previous radar scan but also multiple past radar scans. Note that the ratio between the weights α and β may be changed less or no longer between the left and right columns of FIG. 6.

[0042] In this way, depending on the distance from the radar of the target of interest or the state of motion of the target of interest, it is possible to set which of the scan-to-scan change rates of the predicted and observed Doppler velocities and received power of each target is to be given more importance than the other scan-to-scan change rates.

[0043] Then, taking into consideration that the scan-to-scan rate of change of the predicted and observed Doppler velocities of the target of interest is smaller / larger as the distance of the target of interest from the radar is farther / closer, it is possible to set weighting for the scan-to-scan rate of change of the predicted and observed Doppler velocities and received power of each target. On the other hand, taking into consideration that the scan-to-scan rate of change of the predicted and observed Doppler velocities of the target of interest is small regardless of the distance of the target of interest from the radar, it is also possible to make the ratio of weighting for the scan-to-scan rate of change of the predicted and observed Doppler velocities and received power of each target approximately constant.

[0044] Furthermore, considering that the rate of change in the predicted and observed Doppler velocities of the target between scans is smaller / larger as the target's motion state is at a constant speed / rapid acceleration / deceleration state, the weighting for the rate of change in the predicted and observed Doppler velocities of the target between scans can be set. On the other hand, when the motion state of the target of interest is predicted based on multiple past radar scans, the weighting ratio for the rate of change in the predicted and observed Doppler velocities of the target between scans can be made approximately constant, considering that the rate of change in the predicted and observed Doppler velocities of the target between scans is small regardless of the target's motion state. [Industrial Applicability]

[0045] The radar target tracking device and radar target tracking program disclosed herein, when using radar to track a target such as a ship or aircraft, can reduce the possibility of erroneously linking clutter to a target of interest, even when the density of clutter due to waves, clouds, etc. is high, and can also reduce the possibility of interrupting the tracking process of the target of interest without narrowing the prediction gate of the target of interest. [Explanation of symbols]

[0046] Tv: Focused Target G: Prediction gate T, Ta, Tb, Tc, Td, Te, Tf, Tg, Tn: Target R: Radar target tracking system 1: Radar transmitter and receiver 2: Radar target tracking device 3: Radar display device 11: Target detection section 12:Target memory section 13: Target position prediction unit 14: Scan correlation section 15:Target tracking part

Claims

1. a target detection unit that performs clustering of detection points in each radar scan, detects the position of each target, and detects at least one of an observed Doppler velocity and a received power of each target; a target position prediction unit which predicts the position of each target in each radar scan in preparation for the next radar scan, predicts the Doppler velocity of each target as necessary, and sets a prediction gate for each target centered on the predicted position of each target; an inter-scan correlation unit that calculates, for each target within a prediction gate of a target of interest in each radar scan, a scan-to-scan rate of change from at least one of a predicted Doppler velocity and a received power of the target of interest in a previous radar scan to at least one of an observed Doppler velocity and a received power of the target in each radar scan; a target tracking unit that links, among targets within a prediction gate of the target of interest in each radar scan, a target having the smallest inter-scan change rate to the target of interest; A radar target tracking device comprising:

2. The inter-scan correlation unit, for each target inside the prediction gate of the target of interest in each radar scan, adds a predicted Doppler velocity change rate from the predicted Doppler velocity of the target of interest in the previous radar scan to the observed Doppler velocity of each target in each radar scan and a received power change rate from the received power of the target of interest in the previous radar scan to the received power of each target in each radar scan, with weighting according to the distance of the target of interest from the radar or the motion state of the target of interest, to calculate the inter-scan change rate.

2. The radar target tracking device according to claim 1, wherein:

3. The inter-scan correlation unit (1) increases the weighting for the predicted Doppler velocity change rate compared to the weighting for the received power rate as the distance of the target of interest from the radar increases, and increases the weighting for the received power rate compared to the weighting for the predicted Doppler velocity change rate as the distance of the target of interest from the radar decreases, or (2) keeps a ratio between the weighting for the predicted Doppler velocity change rate and the weighting for the received power rate approximately constant regardless of the distance of the target of interest from the radar.

3. The radar target tracking device according to claim 2, wherein:

4. The inter-scan correlation unit (1) weights the predicted Doppler velocity change rate more heavily as the motion state of the target of interest is a constant velocity state compared to the weights for the received power change rate, while weighting the predicted Doppler velocity change rate more heavily as the motion state of the target of interest is a rapid acceleration / deceleration state compared to the weights for the received power change rate, or (2) sets a substantially constant ratio between the weights for the predicted Doppler velocity change rate and the weights for the received power change rate regardless of the motion state of the target of interest when the target position prediction unit predicts whether the motion state of the target of interest is a constant velocity state or a rapid acceleration / deceleration state based on multiple past radar scans.

3. The radar target tracking device according to claim 2, wherein:

5. 5. A radar target tracking program for causing a computer to execute each processing step executed by each processing unit included in the radar target tracking device according to claim 1.

Images