JP5491981B2 - Radar equipment - Google Patents

Description

  Embodiments described herein relate generally to a radar apparatus that observes the speed of a vehicle by correlation tracking.

  When observing the speed of a vehicle traveling on a road with a radar device, correlation tracking is performed by detecting a target vehicle in the presence of complicated and numerous reflection points such as other vehicles and backgrounds. Under such circumstances, when the antenna beam width is wide and the resolution of the beat frequency axis by the FMCW (Frequency Modulated Continuous Wave) method is low, there are a plurality of reflection points in the main lobe in both the angle axis and the frequency axis. It will be. For this reason, in the conventional method of calculating the distance and the speed by the pairing of the down sweep and the up sweep, a ghost due to a pairing error occurs. The FMCW method is described in, for example, “Supervised by Takashi Yoshida, IEICE,“ Revised Radar Technology ”, pp.274-275 (1996)”.

Supervised by Takashi Yoshida, “Revised Radar Technology”, IEICE, pp.264-267 (1996) Paul R. KALATA, “A Generalized Parameter for α-β, α-β-γ Target Trackers”, IEEE Trans., Pp.174-181, AES VOL.AES-20, N0.2, MARCH 1984

  As described above, in the conventional radar device, the distance and speed are calculated by pairing the down sweep and the up sweep, so that a ghost due to a pairing error occurs and stable correlation tracking cannot be performed. There is.

  An object of the present invention is to provide a radar apparatus that can perform stable correlation tracking without pairing.

  In order to solve the above-described problem, a radar apparatus according to an embodiment uses a transmitter / receiver that repeatedly transmits / receives an FMCW down sweep or up sweep signal, and a beat frequency using an angle measurement value based on the signal from the transmitter / receiver. A beat frequency axis conversion unit that converts coordinates to the fbx-fby axis representing the space of the correlation, and a correlation that performs correlation tracking using the position, velocity, and acceleration in the space of the fbx-fby axis obtained by conversion in the beat frequency axis conversion unit A tracking unit and an XY axis conversion unit that converts a result obtained by correlation tracking in the correlation tracking unit into a position and a speed of an XY axis are provided.

It is a block diagram which shows the structure of the radar apparatus which concerns on 1st Embodiment. It is a flowchart which shows operation | movement of the radar apparatus which concerns on 1st Embodiment. It is a figure which shows the example of the sweep waveform used with the radar apparatus which concerns on 1st Embodiment. It is a figure which shows XY space for demonstrating the error which arises in the radar apparatus which concerns on 1st Embodiment. It is a figure which shows fbx-fby space for demonstrating the error which arises in the radar apparatus which concerns on 1st Embodiment. It is a figure for demonstrating the example of the error which arises in the radar apparatus which concerns on 1st Embodiment. It is a figure for demonstrating the principle which an error produces in the radar apparatus which concerns on 1st Embodiment. It is a figure for demonstrating the error which remains in the radar apparatus which concerns on 1st Embodiment. It is a block diagram which shows the structure of the radar apparatus which concerns on 2nd Embodiment. It is a flowchart which shows operation | movement of the radar apparatus which concerns on 2nd Embodiment. It is a block diagram which shows the structure of the radar apparatus which concerns on 3rd Embodiment. It is a flowchart which shows operation | movement of the radar apparatus which concerns on 3rd Embodiment. It is a figure for demonstrating operation | movement of the radar apparatus which concerns on 3rd Embodiment. It is a figure for demonstrating the correlation tracking performed with the radar apparatus which concerns on 1st-3rd embodiment.

  Hereinafter, embodiments will be described in detail with reference to the drawings.

(First embodiment)
A method adopted in the radar apparatus according to the first embodiment is called FSAT (Frequency Space Data Association and Tracking). FIG. 1 is a system diagram showing the configuration of the radar apparatus according to the first embodiment. The radar apparatus includes an antenna 10, a transceiver 20 and a signal processor 30.

  The antenna 10 includes an antenna transmitting element 11 and a plurality of antenna receiving elements 12. The antenna transmission element 11 converts an electric signal sent as a transmission signal from the transceiver 20 into a radio wave and sends it out. The plurality of antenna receiving elements 12 receive external radio waves, convert them into electrical signals, and send them to the transceiver 20 as received signals.

  The transceiver 20 includes a transmitter 21 and a plurality of mixers 22, and the plurality of mixers 22 are provided corresponding to the plurality of antenna receiving elements 12, respectively. In the case of the FMCW method using general up-chirp and down-chirp signals as transmission signals, a transmission signal swept by the transmitter 21 is generated and sent to the antenna transmission element 11 and the plurality of mixers 22. The plurality of mixers 22 frequency-convert the received signals received from the plurality of antenna receiving elements 12 in accordance with the signal from the transmitter 21 to generate beat frequency signals, and send them to the signal processor 30.

  The signal processor 30 includes an AD converter 31, an FFT unit 32, a DBF unit 33, a detection unit 34, an angle measurement unit 35, a beat frequency axis conversion unit 36, a correlation tracking unit 37, and an XY axis conversion unit 38. Yes.

  The AD converter 31 converts the beat frequency signal sent as an analog signal from the transmitter / receiver 20 into a digital signal, and sends it to the FFT unit 32 as an element signal. The FFT unit 32 converts the element signal sent from the AD converter 31 into a signal on the frequency axis by fast Fourier transform, and sends it to the DBF unit 33.

  The DBF unit 33 uses the signals on the frequency axis sent from the FFT unit 32 to form a Σ beam and a Δ beam. The Σ beam formed by the DBF unit 33 is sent to the detecting unit 34, and the Δ beam is sent to the angle measuring unit 35.

  The detection unit 34 detects the distance and speed based on the Σ beam sent from the DBF unit 33 and sends values representing them to the beat frequency axis conversion unit 36. In addition, the detection unit 34 sends the Σ beam sent from the DBF unit 33 to the angle measurement unit 35.

  The angle measurement unit 35 performs angle measurement by the phase monopulse angle measurement method using the Σ beam transmitted from the detection unit 34 and the Δ beam transmitted from the DBF unit 33. The phase monopulse angle measurement system is described in, for example, “The Institute of Electronics, Information and Communication Engineers,“ Revised Radar Technology ”, pp. 262-264 (1996)”.

The beam in the case of phase monopulse angle measurement can be expressed by the following equation.

here,
bm (θ); Σ beam output en (θ); element pattern (n = 1 to N)
Wm (θ); complex weight (n = 1 to N)
n: Element number (n = 1 to N)
λ: Wavelength
In the case of phase monopulse angle measurement, angle measurement can be performed using a Δ beam of the following equation.

here,
Δm (θ); Δ beam output en (θ); element pattern Wm (n); complex weight (n = 1 to N)
n: Element number (n = 1 to N)
λ: Using the wavelengths bm and Δm, the error voltage ε can be expressed by the following equation.

here,
*: Complex conjugate The angle measurement value can be calculated using the error voltage ε and a correspondence table (or polynomial approximation value) of the error voltage ε and the angle measurement value θ stored in advance. The angle measurement value calculated by the angle measurement unit 35 as described above is sent to the beat frequency axis conversion unit 36.

The beat frequency axis conversion unit 36 performs beat frequency axis conversion based on the value representing the distance and speed sent from the detection unit 34 and the angle measurement value sent from the angle measurement unit 35. Here, if the signals of the Σ beam and the Δ beam are represented by the beat frequency fb, the beat frequency fb can be expressed as follows.

here,
fb: Beat frequency B: Frequency band T: Sweep time R: Distance c: Light speed V: Speed λ: Wavelength kr: 2B / (Tc)
kv: λ / 2
It is as follows when it expresses with the derivative of beat frequency fb, and also the derivative.

These can be expressed as distance R, velocity V, and acceleration A as follows.

here,
R: Distance V: Speed A: Acceleration This can be converted into an XY axis using the measured angle value θ.

here,
fb; Beat frequency θ; Angle measurement value The result (fbx and fby) of the coordinate conversion into fbx-fby in the beat frequency axis conversion unit 36 in this way is sent to the correlation tracking unit 37.

  The correlation tracking unit 37 executes the correlation tracking process using the position, velocity, and acceleration in the space of fbx and fby sent from the beat frequency axis conversion unit 36.

The above-described fbx and fby can be expressed by the following equations when assuming a uniform acceleration motion (the time derivative of acceleration is 0) using the first and second derivatives.

  If fbx and fby velocity (1st derivative) and acceleration (2nd derivative) are observed, the position (xs, ys) and velocity (vxs, vys) are substituted into equations (8) and (9). Can be calculated.

The speeds and accelerations of fbx and fby are expressed by the following equations using, for example, an αβγ filter (see FIG. 14). Note that the αβγ filter is described as a tracking filter in Non-Patent Document 1 and Non-Patent Document 2, for example, and should be referred to as necessary.

The initial values are as follows.

  A smooth value is calculated using this correlation tracking, and a position (xs, ys) and a velocity (vxs, vys) can be calculated using equations (8) to (10). The smoothed value and the predicted value obtained by the correlation tracking process in the correlation tracking unit 37 are sent to the XY axis conversion unit 38.

  The XY axis conversion unit 38 converts the smooth value and the predicted value sent from the correlation tracking unit 37 into the position and speed of the XY axis and sends them to the outside.

  Next, the operation of the radar apparatus according to the first embodiment will be described with reference to the flowchart shown in FIG. First, signal processing is performed (step S10). Specifically, first, down transmission / reception is performed (step S11). That is, the transmitter / receiver 20 sends the down-sweep transmission signal generated by the transmitter 21 to the antenna transmission element 11 of the antenna 10 and the plurality of mixers 22. The antenna transmission element 11 converts an electric signal sent as a transmission signal from the transceiver 20 into a radio wave and sends it out. The plurality of antenna receiving elements 12 of the antenna 10 receive radio waves from the outside, convert them into electrical signals, and send them to the transceiver 20 as received signals. The plurality of mixers 22 included in the transceiver 20 generate beat frequency signals by frequency-converting received signals received from the plurality of antenna receiving elements 12 in accordance with signals from the transmitter 21, and a signal processor 30. Send to.

  In the signal processor 30, the AD converter 31 converts the beat frequency signal sent as an analog signal from the transceiver 20 into a digital signal, and sends it to the FFT unit 32 as an element signal. The FFT unit 32 converts the element signal sent from the AD converter 31 into a signal on the frequency axis by fast Fourier transform, and sends it to the DBF unit 33. The DBF unit 33 forms a Σ beam and a Δ beam using the signals on the frequency axis sent from the FFT unit 32 and sends them to the detecting unit 34 and the angle measuring unit 35, respectively. The detection unit 34 detects the distance and speed based on the Σ beam sent from the DBF unit 33 and sends values representing them to the beat frequency axis conversion unit 36. In addition, the detection unit 34 sends the Σ beam sent from the DBF unit 33 to the angle measurement unit 35.

  Next, an angle measurement value θb is calculated (step S13). That is, the angle measurement unit 35 measures the angle by the phase monopulse angle measurement method using the Σ beam transmitted from the detection unit 34 and the Δ beam transmitted from the DBF unit 33, and beats the angle measurement value θb. This is sent to the frequency axis converter 36.

  Next, coordinate conversion to fbx-fby is performed (step S14). In other words, the beat frequency axis conversion unit 36 performs beat frequency axis conversion based on the value representing the distance and speed sent from the detection unit 34 and the angle measurement value sent from the angle measurement unit 35, and fbx The result (fbx and fby) obtained by coordinate conversion to −fby is sent to the correlation tracking unit 37.

  Next, a grouping process is performed (step S20). This grouping process is optional and is executed when a plurality of beams are formed. The contents of the grouping process will be described later.

  Next, correlation tracking processing is performed (step S30). This correlation tracking process is executed in the correlation processing unit 37. In the correlation tracking process, a correlation process is first performed (step S31). That is, the NN value is extracted. Next, an initial track is established (step S32). Next, αβγ tracking is performed in the fbx and fby spaces (step S33). That is, smooth values of fbx and fby are calculated. Next, X, Y, Vx, Vy, Ax, and Ay are calculated from the smooth values of fbx and fby (step S34).

  When the above correlation tracking process is completed, a smoothing filter process is then performed (step S40). Thereby, a smooth position and a smooth speed are output. Then, it returns to step S11 of signal processing S10, and the process mentioned above is repeated.

  FIG. 3 shows an example of a sweep waveform used in the first embodiment. The sweep waveform may be either a down sweep or an up sweep, but is generally expressed by a combination of a down sweep and an up sweep. When the sweep within the cycle time for correlation tracking (correlation tracking time interval) is generally N sweep, at the same beat frequency of the FFT waveform of N sweep, after detecting by threshold determination by the result of amplitude integration, In the detection bank (beat frequency bank), the angle measurement for N sweeps is performed, and the angle measurement values are averaged, thereby improving the accuracy of the angle measurement values.

  Further, the above-described grouping process can be configured as follows. In the grouping process, first, combining between a plurality of beams is performed (step S21). That is, the observation values (fbx, fby) between the plurality of beams are combined. Next, grouping is performed (step S22). That is, an extreme value is extracted from the multiple observed values in descending order of amplitude value, a predetermined gate is formed around the beat frequency axis of the extraction point, and the observed value (beat frequency) in the gate is determined. A plurality of points are grouped using a centroid calculation such as weighting by each amplitude value. The grouped result is sent to the correlation tracking unit 37.

  Further, after calculating a smooth value of the position and speed from (fbx, fby), a filter based on the speed of the road shoulder reflection point (vehicle speed), the road shoulder position, etc. is applied to add processing for suppressing unnecessary points. It can also be configured.

  As described above, according to the radar apparatus of the first embodiment, the beat frequency is observed using the repeated sweep of only the down sweep or the up sweep, the correlation tracking is performed in the beat frequency space, and the correlation tracking result is obtained. Since (smooth value and predicted value) are used for conversion to the XY axes, pairing of down sweep and up sweep is unnecessary, and ghost due to erroneous pairing does not occur. As a result, even under complicated background, it is possible to improve the target observation position accuracy and realize stable correlation tracking.

(Second Embodiment)
A method adopted in the radar apparatus according to the second embodiment is called IFSAT (; Improved FSAT). In the radar apparatus according to the first embodiment described above, only one of the down sweep and the up sweep is used. In this case, a non-linear error occurs due to the relationship between the fbx-fby space and the XY space. First, this error will be described.

Assuming that the angle measurement values θ of the XY space and the fbx-fby space are equal, and assuming a constant acceleration motion, the beat frequency fb, its first and second derivatives are expressed as follows. It can be expressed by the following formula.

When the equation (15) is separated into x and y components, it can be expressed by the following equation. However, it is assumed that the motion is equal acceleration (the time derivative of acceleration is 0).

here,
xs, ys: smooth value of position vxs, vys: smooth value of velocity axs, ays: smooth value of acceleration θ: angular value (8) and (16), (9) and (17) are compared To do. If fbx and fby on the left side are equal in both,
(8) Formula → (16) Formula xs → xs · sin θ
vxs → vxs · sinθ
axs → axs · sinθ
Expression (9) → Expression (17) ys → ys · cos θ
vys → bys · cos θ
ays → ays · cos θ
It can be seen that there is an error due to θ. This is because fbx and fby are defined by the relationship of equation (7) from fb and θ, and fbx and fby defined by equations (16) and (17) are different. ) To (14) are errors caused by processing. An example of this error is shown in FIG.

  When the target is constant along the X axis in the down sweep and approaches along the Y axis, in the beat frequency space, the beat frequency component fr according to the distance and the beat frequency due to the speed as shown in FIG. The component fd is added, resulting in a wake that swells outward. This principle is shown in FIG. 7 together with the case of up sweep.

  In the case of the down sweep, the beat frequency fbv by the speed approaching the beat frequency fbr by the distance is the same positive frequency. On the other hand, in the case of up sweep, the beat frequency fbr depending on the distance is a negative frequency, and the beat frequency fbv depending on the approaching speed is a frequency in the positive direction. When this is observed as a positive frequency, it becomes a folded frequency. In the case of the down sweep and the up sweep, the relationship is as shown in FIG. When this is converted into the XY axis by the equations (8) and (9), the above-mentioned error remains, and even if the actual vehicle trajectory is a straight line as shown in FIG. Observed at a slightly deviated position.

Next, a method for correcting this error will be considered. When the trajectory in the down sweep and the up sweep is converted into the XY axis, as shown in FIG. 8B, an error remains in the left and right reverse directions with respect to the true trajectory. By utilizing this shift in the reverse direction, the XY conversion value (xsd, ysd) of the down sweep and the XY conversion value (xsu) of the up sweep, which are outputs after conversion to the XY axes of the down sweep and the up sweep, respectively. , Ysu) is generally within a predetermined gate range, the position accuracy can generally be improved by combining the following equations.

here,
(Xs, ys); position of XY axis after combination (xsd, ysd); position after conversion of XY axis of down sweep (xsu, ysu); position after conversion of XY axis of up sweep Wd ; Weight for down sweep Wu; Weight for up sweep = (1-Wd)
As an example of weighting, Wd = Wu = 0.5 can be obtained by equalizing the down sweep and the up sweep. The IFSAT correction value shown in FIG. 8B is a value obtained by weighting the XY conversion value of the down sweep and the XY conversion value of the up sweep.

  FIG. 9 is a system diagram showing a configuration of a radar apparatus according to the second embodiment for realizing the above-described error correction. This radar apparatus is configured by adding a down-up coupling unit 39 to the signal processing unit 30 of the radar apparatus according to the first embodiment shown in FIG.

  The down-up combination unit 39 combines the smooth value based on the down sweep and the smooth value based on the up sweep sent from the XY axis conversion unit 38 and sends them to the outside.

  Next, the operation of the radar apparatus according to the second embodiment will be described with reference to the flowchart shown in FIG. First, signal processing is performed (step S15). In this signal processing, the processing in step S10 (see FIG. 2) of the first embodiment is changed to down / up signal processing (step S16) in which down sweep and up sweep signals are alternately transmitted and received. Except for this, it is the same as that of the first embodiment.

  Next, a grouping process is performed (step S20). This grouping process is optional as in the first embodiment, and is executed when a plurality of beams are formed.

  Next, correlation tracking processing is performed (step S30). This correlation tracking process is the same as that of the first embodiment described above except that the processes for down sweep and up sweep are performed alternately. Next, the down-up smoothing value combination is performed (step S50), that is, the down-up combining unit 39 receives the smooth value based on the down sweep and the smooth value based on the up sweep sent from the XY axis conversion unit 38. Join.

  Next, smoothing filter processing is performed (step S40). Thereby, a smooth position and a smooth speed are output. Then, it returns to step S16 of signal processing S10, and the process mentioned above is repeated.

  As the gate, in addition to the position gate, a speed gate is used to add a condition that (vxd, byd) and (vxu, vyu), which are down sweep and up sweep speeds, are within a predetermined range. It can be configured as follows.

  As described above, according to the radar apparatus according to the second embodiment, the results obtained by the radar apparatus according to the first embodiment for each of the down sweep and the up sweep are used on the XY axis. Since the correlation is taken and weighted and averaged, the accuracy of position and velocity can be improved.

(Third embodiment)
A method adopted in the radar apparatus according to the third embodiment is called AFSAT (Advanced FSAT). Since the radar apparatus according to the second embodiment described above uses a combination of down sweep and up sweep positions, a position with corrected error can be calculated.

  The radar apparatus according to the third embodiment calculates a position with higher accuracy. In the conventional radar apparatus, there is a problem that a ghost is generated due to erroneous pairing. However, if the pairing is correct, a position with higher accuracy can be calculated. Here, for the sake of simplicity, a distance measuring method using pairing by down sweep and up sweep is referred to as MPAT (Measured Pairing Data Association and Tracking).

  FIG. 11 is a block diagram showing a configuration of a radar apparatus using the MPAT method. This radar apparatus is configured by adding a pairing processing unit 40 and a correlation tracking unit 41 to the signal processing unit 30 of the radar apparatus according to the second embodiment shown in FIG.

The pairing processing unit 40 acquires angle measurement values for each of the down sweep and the up sweep from the angle measurement unit 35, and performs pairing when both angle measurement values are within a predetermined range, using the equation (19). To calculate distance and speed. The distance and speed calculated by the pairing processing unit 40 are sent to the correlation tracking unit 41.

here,
B; frequency band R; target distance T; sweep time c; speed of light V; target speed λ; wavelength Δf1; observation frequency of down-chirp signal Δf2; observation frequency of up-chirp signal fd; Doppler frequency fr; 41 performs correlation tracking based on the distance and speed sent from the pairing processing unit 40, calculates a smooth value of the distance and speed, and sends it to the down-up combination unit 39. As shown in FIG. 13, the smooth value includes an MPAT ghost m that is a ghost due to erroneous pairing. In order to eliminate this, the position X− calculated in the second embodiment is used. A correlation gate cg is formed with Y (IFSAT) a as the center, and when XY (MPAT) m calculated by pairing is within the correlation gate, the result of XY (IFSAT) a is replaced. Further, in order to prevent a step from being generated due to the difference in the position of XY at the time of replacement, the XY values of IFSAT and MPAT are weighted as shown in the following equation.

here,
(Xs, ys); position of XY axis after combination (xsa, ysa); position of XY axis of IFSAT (xsm, ysm); position of XY axis of MPAT Wa; weighting to IFSAT Wm ; Weighting for MPAT = (1-Wa)
As an example of weighting, if IFSAT and MPAT are made equal, Wa = Wm = 0.5 may be set.

  It should be noted that, when the correlation between IFSAT and MPAT is taken, a condition that both speeds are within a predetermined range can be added.

  Next, the operation of the radar apparatus according to the third embodiment will be described with reference to the flowchart shown in FIG.

  First, signal processing is performed (step S17). This signal processing is performed in step S15 (see FIG. 10) of the second embodiment, except that angle gate processing (step S18) and first pairing processing (step S19) are added to the processing in step S17. ) Is the same as the signal processing performed in (1). In this signal processing, first, similarly to the above-described second embodiment, processing of step S16 → step S12 → step S13 → step S14 is performed.

  Next, a grouping process is performed (step S20). This grouping process is optional as in the first embodiment, and is executed when a plurality of beams are formed. Next, correlation tracking processing is performed (step S30). This correlation tracking process is the same as that of the second embodiment described above.

  Next, down / up smoothing value combination (short distance) is performed (step S50), that is, the down-up combination unit 39 performs smoothing and up sweep based on the down sweep sent from the XY axis conversion unit 38. Combine smooth values based on.

  In parallel with the processes in steps S17, S20, S30, and S40, the following processes are performed. That is, in the signal processing, when the processing in step S14 is completed, angle gate processing is performed (step S18). That is, the pairing processing unit 40 forms a correlation gate. Next, a first pairing process is performed (step S19). That is, the pairing processing unit 40 obtains the angle measurement values for each of the down sweep and the up sweep from the angle measurement unit 35, and pairs the distance measurement values in a predetermined range to determine the distance and speed. Calculate and send to the correlation tracking unit 41.

  Next, a grouping process is performed (step S20a). This grouping process is optional as in the first embodiment, and is executed when a plurality of beams are formed. Next, correlation tracking processing is performed (step S30a). This correlation tracking process is obtained by removing the process of step S30 from the process of step S34 described above, that is, the process of calculating X, Y, Vx, Vy, Ax, and Ay from the smooth values of fbx and fby.

  Next, if there is a correlation, a replacement process is performed (step S60). That is, the correlation tracking unit 41 replaces the result of XY (IFSAT) i when XY (MPAT) m calculated by pairing is in the correlation gate cg.

  Next, smooth value combination is performed (step S70). That is, the down-up combiner 39 is further sent from the correlation tracking unit 41 to the result of combining the smooth value based on the down sweep and the smooth value based on the up sweep sent from the XY axis converter 38. Combine smooth values.

  Next, a smooth value filter is performed (step S40). Then, it returns to step S16 and the process mentioned above is repeated.

  As described above, according to the radar apparatus according to the third embodiment, the result obtained by the radar apparatus according to the second embodiment and the observed value of the pairing result by the down sweep and the up sweep are used. Since the correlation with the result of the correlation tracking is obtained, the accuracy of the position and speed can be improved while suppressing the ghost due to the erroneous pairing of the down sweep up sweep.

  Note that the radar apparatus according to the third embodiment described above is designed to improve accuracy by applying pairing to the radar apparatus according to the second embodiment, but according to the first embodiment. The radar apparatus can also be configured to improve accuracy by applying pairing.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 10 Antenna 11 Antenna transmission element 12 Multiple antenna receiving elements 20 Transmitter / receiver 21 Transmitter 22 Multiple mixers 30 Signal processor 31 AD converter 32 FFT section 33 DBF section 34 Detection section 35 Angle measurement section 36 Beat frequency axis conversion section 37 Correlation tracking unit 38 XY axis conversion unit 39 Down-up coupling unit 40 Pairing processing unit 41 Correlation tracking unit

Claims (4)

A transceiver that repeatedly transmits and receives a FMCW down sweep or up sweep signal;
A beat frequency axis conversion unit that converts coordinates to an fbx-fby axis that represents a beat frequency space using an angle measurement value based on a signal from the transceiver;
A correlation tracking unit that performs correlation tracking using position, velocity, and acceleration in the space of the fbx-fby axis obtained by the conversion in the beat frequency axis conversion unit;
An XY axis conversion unit that converts a result obtained by correlation tracking in the correlation tracking unit into an XY axis position and velocity;
A radar apparatus comprising: A transceiver that repeatedly transmits and receives FMCW down-sweep and up-sweep signals;
In each of the down sweep and up sweep signals from the transmitter / receiver, a beat frequency axis conversion unit that performs coordinate conversion to an fbx-fby axis that represents a beat frequency space using an angle measurement value based on the signal;
A correlation tracking unit that performs correlation tracking using position, velocity, and acceleration in the space of the fbx-fby axis obtained by the conversion in the beat frequency axis conversion unit;
An XY axis conversion unit that converts a result obtained by correlation tracking in the correlation tracking unit into an XY axis position and velocity;
If the difference between at least one of the down sweep and the up sweep position or speed obtained by the X-Y axis converter is equal to or smaller than a predetermined value, the down is obtained by weighting and combining the position, speed or acceleration. An up coupling,
A radar apparatus comprising: A pairing processing unit for pairing those whose angle measurement values for each of the down sweep and the up sweep are within a predetermined range;
Another correlation tracking unit that calculates a smooth value of the distance and speed by performing correlation tracking by the distance and speed obtained by pairing in the pairing processing unit,
If the difference between the smooth value obtained by the other correlation tracking unit and the position and speed of the smooth value obtained by the correlation tracking unit is equal to or smaller than a predetermined value, the down-up coupling unit 3. The radar apparatus according to claim 2, wherein a value obtained by combining the speed or acceleration is obtained. A pairing processing unit for pairing an angle measurement value for a down sweep or an up sweep within a predetermined range;
Another correlation tracking unit that performs correlation tracking based on the distance and speed obtained by pairing in the pairing processing unit and calculates a smooth value of the distance and speed;
If the difference between at least one of the smoothed value obtained by the other correlation tracking unit and the smoothed value obtained by the correlation tracking unit is less than or equal to a predetermined value, the position, velocity or acceleration is weighted. The radar apparatus according to claim 1, further comprising a down-up combination unit that obtains a combined value.

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