JP2009103566A - Measuring device and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To surely detect an object, even if interference is generated, for example, by multipath or the like, by a vehicle surface shape or a road surface. <P>SOLUTION: A two-frequency CW radar 1 executes measurement processing of a high-speed measuring mode, to thereby output a high-speed measurement result Sh, and executes measurement processing of a low-speed measuring mode, to thereby output a low-speed measurement result Sl. A processing calculating device 2 executes a prescribed processing, by using the high-speed measurement result Sh from the two-frequency CW radar 1; and when it is determined that interference of a reception signal is generated, it continues the prescribed processing on reference to the low-speed measurement result Sl, rather the high-speed measurement result Sh, to thereby enable sure detection of a measuring object 3. The present invention is applicable to high-response systems, such as, pre-crash systems. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a measurement apparatus and method, and more particularly, to a measurement apparatus and method that can reliably detect an object.

  2. Description of the Related Art Conventionally, a two-frequency CW (Continuous Wave) type sensor (hereinafter referred to as a two-frequency CW radar) is known as a sensor for measuring the relative speed and distance between the own vehicle and another vehicle (for example, Patent Documents). 1 and 2). That is, this two-frequency CW radar detects the frequency (hereinafter referred to as “Doppler frequency”) and phase of the reflected signal from the object of the transmission signal, and uses the detection result to detect the relative speed of the other vehicle. Measure distance.

  The automobile (own vehicle) is equipped with an ACC (adaptive cruise control) system that can automatically follow the distance between the preceding vehicle (other vehicles) using a sensor such as a two-frequency CW radar. Has been. Also, in recent years, a pre-crash system has been installed to detect the possibility of collision between the vehicle and another vehicle (pre-crash) using such a sensor such as a two-frequency CW radar and reduce the impact at the time of collision. It has been.

As described above, a plurality of systems having different applications using signals from sensors have been mounted on automobiles.
Japanese Patent No. 3203600 JP 2004-69693 A

  However, when the object is captured by the on-vehicle radar, a phenomenon in which the power greatly fluctuates due to multipath from the road surface or interference due to the surface shape of the object. When trying to track the relative position of an object, information on the object being tracked may be overlooked due to this power fluctuation, and the object may be lost.

  Also, when using on-vehicle radar for danger detection, for example, there is a vehicle in a dangerous area, and even in situations where it must be determined that it is dangerous, the received power is reduced due to fading and interference, There was also a situation where information about the object could not be obtained.

  The present invention has been made in view of such a situation. For example, an object can be reliably detected even when interference occurs due to a vehicle surface shape or a multipath caused by a road surface. .

  A measuring apparatus according to one aspect of the present invention is a measuring apparatus that measures a target by a Doppler method using a Doppler signal for a reflected signal at a target of a transmission signal. As a measurement mode in which the frequency analysis is performed and the object is measured by the Doppler method using the frequency analysis result, the first measurement mode in which the collection time for obtaining the collection data from the reflected signal is the first time. And a second measurement mode in which the collection time is a second time longer than the first time, and a first measurement processing means for executing a measurement process in the first measurement mode, Second measurement processing means for executing measurement processing in two measurement modes, and processing operation means for executing predetermined processing using the first measurement result in the first measurement mode, The measurement process of the measurement mode and the measurement process of the second measurement mode are performed independently and in parallel, and when the processing calculation unit determines that interference of the reflected signal has occurred, Instead of the first measurement result, a predetermined process is executed using the second measurement result in the second measurement mode.

  As a result, even if interference occurs due to, for example, the vehicle surface shape or the multipath due to the road surface, it becomes possible to achieve both high-speed response and accuracy of the measurement processing by the Doppler method, and use the measurement results later. The process can be executed properly.

  For example, as the Doppler method, a two-frequency CW method, a monopulse method, or the like can be adopted.

  For example, the first measurement processing means and the second measurement processing means are constituted by a two-frequency CW radar, a monopulse radar (including a radar including both functions), or the like, and the processing calculation means is a microcomputer or the like. Composed.

  When it is determined that the reflected signal has converged, the processing calculation unit performs a predetermined process using the first measurement result instead of the second measurement result.

  The processing calculation means performs the tracking process of the object using the first measurement result, and when the tracking of the object that has been tracked becomes impossible, the process is not performed instead of the first measurement result. The tracking process is performed using the second measurement result.

  The processing calculation means performs a tracking process of the object based on the measured relative speed and distance of the object, and the first measurement result is obtained when a change width of the distance is larger than a predetermined threshold. Instead, the tracking process is performed using the second measurement result.

  As a result, for example, in the case of tracking processing based on target information obtained by normal signal processing, when an object cannot be detected suddenly, the calculation result or tracking in the low-speed measurement mode with high detection performance By referring to the result, it is possible to keep tracking without losing sight of the object.

  The processing calculation means executes a predetermined process using the second measurement result instead of the first measurement result when the power of the reflected signal falls below a predetermined threshold.

  Thereby, even if interference occurs due to, for example, the vehicle surface shape or the multipath on the road surface, and the phenomenon that the power greatly fluctuates, information about the object can be obtained with certainty.

  A measuring method according to one aspect of the present invention is a measuring method of a measuring apparatus that measures a target by a Doppler method using a Doppler signal for a reflected signal of a transmission signal on a target, and the sampling acquired from the reflected signal As a measurement mode for performing frequency analysis on data and measuring an object by the Doppler method using the frequency analysis result, a first time for obtaining the collection data from the reflected signal is a first time. And a second measurement mode in which the sampling time is a second time longer than the first time, the measurement process in the first measurement mode is executed, and the second measurement mode is executed. Including a step of executing a measurement process in the measurement mode and executing a predetermined process using the first measurement result in the first measurement mode, the measurement process in the first measurement mode, and the second The measurement process in the measurement mode is performed independently and in parallel, and when it is determined that interference of the reflected signal has occurred, the second measurement mode is replaced with the second measurement mode instead of the first measurement result. A predetermined process is executed using the measurement result.

  As a result, even if interference occurs due to, for example, the vehicle surface shape or the multipath due to the road surface, it becomes possible to achieve both high-speed response and accuracy of the measurement processing by the Doppler method, and use the measurement results later. The process can be executed properly.

  For example, as the Doppler method, a two-frequency CW method, a monopulse method, or the like can be adopted.

  As described above, according to one aspect of the present invention, an object can be reliably detected even when interference occurs due to, for example, a vehicle surface shape or a multipath caused by a road surface.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  By the way, the inventor of the present invention has analyzed the cause of occurrence of the above-described conventional problems, and invented a measurement system (measurement apparatus) capable of solving the conventional problems based on the analysis result. Therefore, before describing the present embodiment, the analysis result, that is, the cause of occurrence of the conventional problem will be described.

  First, the cause of the interference caused by the in-vehicle radar will be described with reference to FIG. 1 so that the cause of the occurrence of the conventional problem can be easily understood.

  As shown in the schematic diagram on the upper side of FIG. 1, a radar 1 provided in a vehicle (own vehicle) transmits a transmission signal having a predetermined frequency to be transmitted to a vehicle (another vehicle) traveling in front of the vehicle. The transmission signal is recognized by using the reflected signal (received signal) reflected from the other vehicle, but interference occurs due to the surface shape of the other vehicle as shown by the multiple straight lines in the figure. There are things to do.

  In addition, as shown in the schematic diagram on the lower side of FIG. 1, the received signals may interfere with each other due to multipath or the like on the road surface on which the vehicle is traveling.

  Here, paying attention to the power fluctuation of the received signal when such interference occurs, the time-series change of the voltage value due to the received signal received by the radar 1 is as shown in FIG. When converted, the result is as shown in FIG. That is, in FIG. 3, there is a phenomenon in which the power greatly fluctuates due to the surface shape of other vehicles and interference due to multipath from the road surface.

  For example, when a process of tracking an object occurs, if a phenomenon in which the power of the received signal fluctuates greatly occurs, there is a possibility that information on the object being tracked may be lost due to the power fluctuation. That is, as described with reference to FIGS. 1 to 3, when the radar 1 acquires a reception signal from another vehicle, the power fluctuates due to interference between reflected waves due to the vehicle surface shape and multipath. When the power is minimized due to interference, the signal-to-noise ratio (SNR) decreases, and target information cannot be obtained, and the object may be lost. That is, the conventional problem occurs.

  Therefore, the inventor of the present invention has invented the following method in order to solve such a conventional problem. That is, in the present invention, focusing on the fact that the power fluctuation occurs along the time axis, when the power fluctuation occurs, only the data of the time when the power is minimized is used by taking a long sampling time of the signal. This is a method of not performing the calculated operation.

  That is, in the present invention, the calculation using the long-time sampling data is performed at the same time as the calculation using the short-time sampling data with an emphasis on responsiveness, and the target is determined by the decrease in the S / N ratio based on the calculation result based on the short-time sampling data. When the information is lost, it is decided to complement it by using the result of long-time sampling.

  Therefore, hereinafter, a measurement system to which such a technique is applied will be described with reference to the drawings from FIG.

  Various radars can be used as the radar 1 used in such a measurement system. In the present embodiment, a radar that performs measurement by the two-frequency CW method (hereinafter referred to as the two-frequency CW radar 1). The case where is adopted will be described.

  FIG. 4 shows a configuration example of an embodiment of a measurement system to which the present invention is applied.

  The measurement system shown in FIG. 4 includes a two-frequency CW radar 1 and a processing arithmetic device 2. The processing arithmetic device 2 can be constituted by a microcomputer or the like, for example.

  The two-frequency CW radar 1 can perform measurement by the two-frequency CW method as the name suggests.

  Here, an outline of measurement by the two-frequency CW method will be described.

  The two-frequency CW radar 1 generates a signal (hereinafter referred to as a two-frequency CW) obtained as a result of switching between a CW (Continuous Wave) having a frequency f1 and a CW having a frequency f2 in a time division manner. Output as a transmission signal Ss.

  The transmission signal Ss is reflected by the measurement object 3, and the reflected signal is received by the two-frequency CW radar 1 as the reception signal Sr.

  At this time, if a relative speed v exists between the two-frequency CW radar 1 and the measurement object 3, Doppler frequencies Δf1 and Δf2 are generated for the frequencies f1 and f2 of the transmission signal Ss, respectively. As a result, the frequency of the reception signal Sr becomes the frequency f1 + Δf1, f2 + Δf2. In other words, a two-frequency CW having two frequencies f1 + Δf1, f2 + Δf2 is a signal equivalent to the received signal Sr.

  Therefore, the two-frequency CW radar 1 detects the Doppler frequency Δf1 or Δf2 from the received signal Sr and performs the calculation of the following equation (1) or equation (2), thereby The relative speed v of the measurement object 3 can be obtained.

v = c × Δf1 / (2 × f1) (1)
v = c * [Delta] f2 / (2 * f2) (2)
Note that c represents the speed of light.

  Further, the two-frequency CW radar 1 detects the phase φ1 of the Doppler signal having the Doppler frequency Δf1 and the phase φ2 of the Doppler signal having the Doppler frequency Δf2 from the reception signal Sr, and the following equation (3) By performing this calculation, the distance L between the two-frequency CW radar 1 and the measurement object 3 can be obtained.

  L = c × (φ1−φ2) / (4π × (f1−f2)) (3)

  The measurement performed by such a series of processes is a measurement by the two-frequency CW method.

  As described above, in the two-frequency CW method, it is necessary to detect the Doppler frequencies Δf1 and Δf2 and the phases φ1 and φ2 corresponding to them. This detection is realized by subjecting the corresponding Doppler signal to frequency analysis processing, for example, FFT (Fast Fourier Transform) analysis processing (hereinafter simply referred to as FFT).

  One factor that determines the accuracy of the FFT is the data amount (the number of waves in terms of an analog waveform) of a waveform (hereinafter referred to as a processing target waveform) to be subjected to the FFT. That is, it is known that the accuracy of the FFT improves as the data amount of the processing target waveform increases. In other words, it can be said that if the data amount of the processing target waveform decreases, the accuracy of the FFT deteriorates.

  Therefore, in this embodiment, as a measurement mode for performing measurement processing of relative speed and distance by the two-frequency CW method, a plurality of measurement modes having different FFT processing times, that is, FFT processing target waveforms (Doppler frequency Δf1). , .DELTA.f2 Doppler signal) is provided with measurement modes having different sampling times and executed in parallel with each measurement process in a plurality of measurement modes (hereinafter referred to as a multiple FFT mode technique). ) Is adopted.

  As for the invention of the multiple FFT mode technique, the present applicant has already filed a patent application as Japanese Patent Application No. 2006-310603.

  By the way, the response speed and accuracy of a plurality of measurement modes in this case depend on each processing time of FFT. That is, the measurement mode in which the FFT processing time is short has a feature that it has high-speed response but low accuracy. On the other hand, the measurement mode in which the FFT processing time is long has a feature that it has a low speed response but is highly accurate.

  In the present embodiment, the following first measurement mode and second measurement mode are provided as measurement modes. The first measurement mode refers to a measurement mode in which measurement processing is performed from short-time collected data, that is, a measurement mode in which FFT processing time is short. On the other hand, the second measurement mode refers to a measurement mode in which measurement processing is performed from long-time collected data, that is, a measurement mode in which FFT processing time is long.

  Hereinafter, the first measurement mode is referred to as a high-speed measurement mode, and the second measurement mode is referred to as a low-speed measurement mode.

  An example of a two-frequency CW radar that uses the high-speed measurement mode and the low-speed measurement mode is the two-frequency CW radar 1 in FIG.

  That is, the two-frequency CW radar 1 measures the relative speed Vh, the distance Lh, and the power Ph of the measurement object 3 using the short-time sampling data from the reception signal Sr as measurement processing in the high-speed measurement mode, and uses them. A series of processing is executed until a signal Sh including the signal Sh (hereinafter referred to as a high-speed measurement result Sh) is generated and output. In parallel with the measurement process in the high speed mode, the two-frequency CW radar 1 uses the long-time sampling data from the received signal Sr as the measurement process in the low speed measurement mode, and the relative speed Vl, distance Ll, The power Pl is measured, and a series of processes from generation and output of a signal Sl including them (hereinafter referred to as a low speed measurement result Sl) is executed.

  As shown in FIG. 4, the high-speed measurement result Sh and the low-speed measurement result Sl are provided to the processing arithmetic device 2. However, the high-speed measurement result Sh and the low-speed measurement result S1 are not necessarily provided to the processing arithmetic unit 2 at the same time, and are independently provided for each measurement process in the high-speed measurement mode. The low speed measurement result S1 is provided to the processing arithmetic unit 2 each time it is provided to the processing arithmetic unit 2 and for each measurement process in the low speed measurement mode. That is, while one low speed measurement result S1 is provided to the processing arithmetic device 2, more high speed measurement results Sh are provided to the processing arithmetic device 2.

  Therefore, the processing arithmetic device 2 can execute high-speed processing using the high-speed measurement result Sh, while executing high-precision processing using the low-speed measurement result S1.

  As described above, the measurement system includes the two-frequency CW radar 1 and the processing arithmetic unit 2. First, details of a series of processing examples of the two-frequency CW radar 1 will be described with reference to FIGS. Details of a series of processing examples of the processing operation device 2 will be described later with reference to FIGS. 8 to 14.

  First, the detailed configuration of the two-frequency CW radar 1 will be described with reference to FIG.

  The two-frequency CW radar 1 in the example of FIG. 5 is configured to include the oscillating unit 11 to the calculation control unit 24.

  The oscillating unit 11 oscillates by alternately switching the CW of the frequency f1 and the CW of the frequency f2 based on the control of the arithmetic control unit 24. That is, a two-frequency CW having frequencies f1 and f2 is output from the oscillation unit 11 and provided to the amplification unit 12.

  The amplifying unit 12 appropriately performs various processes such as an amplifying process on the two-frequency CW, and provides it to the branching unit 13.

  The branching unit 13 provides the two-frequency CW from the amplifying unit 12, that is, the two-frequency CW having the frequencies f1 and f2, to the amplifying unit 14 and the mixing unit 18, respectively.

  The amplifying unit 14 appropriately performs various processing such as amplification processing on the two-frequency CW from the branching unit 13, that is, the two-frequency CW having the frequencies f1 and f2, and outputs the resulting signal to the antenna unit 15 as an output signal. provide. An output signal of the amplifying unit 14 is output from the antenna unit 15 in the form of a radio wave as a transmission signal Ss.

  The two-frequency CW is output from the antenna unit 15 as a transmission signal Ss after being modulated by a predetermined modulation method as necessary. It is assumed that this modulation process is executed in the amplification unit 14, for example.

  The transmission signal Ss is reflected by the measurement object 3, and the reflected signal is received by the antenna unit 16 as the reception signal Sr.

  In the example of FIG. 5, the transmitting antenna unit 15 and the receiving antenna unit 16 are provided separately. However, it is also possible to provide one antenna unit that uses both transmitting and receiving. Good.

  The amplifying unit 17 appropriately performs various processes such as an amplifying process on the received signal Sr received by the antenna unit 16, and provides the resultant two-frequency CW to the mixing unit 18 as an output signal. When the amplification unit 14 is executing the modulation process, the amplification unit 17 further executes a demodulation process corresponding to the modulation process in order to obtain the above-described two-frequency CW.

  As described above, the two-frequency CW output from the amplifying unit 17, that is, the two-frequency CW obtained from the reception signal Sr, has the frequency f1 + Δf1 and the frequency f2 + Δf2. That is, from the amplifying unit 17, it is as if the CW of the frequency f1 + Δf1 and the CW of the frequency f2 + Δf2 are alternately switched in time division and sequentially output.

  The mixing unit 18 has a two-frequency CW output from the amplifying unit 17 (a two-frequency CW having frequencies f1 + Δf1, f2 + Δf2) and a two-frequency CW output from the branch unit 13 (frequency f1, f2). 2 frequency CW) and the resulting mixed signal Smix, specifically, for example, a mixed signal Smix having a waveform shown in FIG.

  Based on the control of the switching timing unit 19, the switch unit 20 switches the output destination from one of the amplification unit 21-1 and the amplification unit 21-2 to the other. That is, the switching timing unit 19 monitors the switching timing of the oscillation frequencies f1 and f2 of the oscillating unit 11 by the arithmetic control unit 24, and the output destination of the switching unit 20 is amplified at the timing when the frequency is switched from f2 to f1. The output destination of the switch unit 20 is switched to the amplification unit 21-2 side at a timing when switching to the -1 side and the frequency is switched from f1 to f2.

  That is, of the mixed signal Smix, the signal output from the mixing unit 18 while the oscillating unit 11 oscillates the CW having the frequency f1 is provided to the amplification unit 21-1 via the switch unit 20 and amplified. Various processing such as processing is appropriately performed, and further, a high-frequency component (noise or the like) is removed by the low-pass filter unit 22-1, and then provided to the A / D conversion unit 23 as a signal SΔf1. This signal SΔf1 is a Doppler signal having a Doppler frequency Δf1.

  On the other hand, of the mixed signal Smix, a signal output from the mixing unit 18 while the oscillating unit 11 oscillates CW having the frequency f2 is provided to the amplifying unit 21-2 via the switch unit 20 and amplified. Various processing such as processing is appropriately performed, and further, a high-frequency component (noise or the like) is removed by the low-pass filter unit 22-2, and then provided to the A / D conversion unit 23 as a signal SΔf2. This signal SΔf2 is a Doppler signal having a Doppler frequency Δf2.

  That is, as shown in FIG. 6, the mixed signal Smix output from the mixing unit 18 is converted into the Doppler signal SΔf1 having the Doppler frequency Δf1 and the Doppler frequency by the switching timing unit 19 to the low-pass filter unit 22-2. Separated into Doppler signals SΔf2 having Δf2 and provided to the A / D converter 23, respectively.

  The A / D conversion unit 23 performs A / D conversion (Analog to Digital conversion) processing on the Doppler signal SΔf1 having the Doppler frequency Δf1 and the Doppler signal SΔf2 having the Doppler frequency Δf2. And the digital Doppler signal SΔf1 and the Doppler signal SΔf2 obtained as a result are provided to the arithmetic control unit 24.

  A detailed configuration example of the arithmetic control unit 24 is shown in FIG. In the example of FIG. 7, the arithmetic control unit 24 is configured to include a control unit 51 to a low-speed measurement mode measurement processing unit 54.

  The control unit 51 performs control in the arithmetic control unit 24 and controls the entire two-frequency CW radar 1, for example, as described above, the frequency of CW oscillated by the oscillation unit 11 is changed from one of f1 and f2 to the other. Control to switch to.

  The data acquisition / holding unit 52 sequentially provides the Doppler signal SΔf1 having the Doppler frequency Δf1 and the Doppler signal SΔf2 having the Doppler frequency Δf2, which are sequentially provided in the form of digital data from the A / D conversion unit 23. Each of these is acquired and held individually. The data holding amount in the data acquisition holding unit 52 is not particularly limited as long as it is equal to or larger than the data amount necessary for one measurement process of the low-speed measurement mode measurement processing unit 54 described later.

  The high-speed measurement mode measurement processing unit 53 uses the data held in the data acquisition and holding unit 52 during the time TH (for example, 50 msec), executes the measurement process once, and obtains the high-speed measurement result Sh obtained as a result. Is output. For this reason, the high-speed measurement mode measurement processing unit 53 is provided with a high-speed FFT unit 61 and a high-speed speed distance calculation unit 62.

  The high speed FFT unit 61 collects data held in the data acquisition holding unit 52 during the collection time TH. That is, the data acquisition and holding unit 52 performs the sampling time TH immediately before the data of the Doppler signal SΔf1 having the Doppler frequency Δf1 and the Doppler signal SΔf2 having the Doppler frequency Δf2. The data acquired and held is collected by the high-speed FFT unit 61.

  Then, during the measurement processing time (calculation time) TC, the following measurement processing is executed by the high-speed FFT unit 61 and the high-speed speed distance calculation unit 62.

  That is, the high-speed FFT unit 61 performs, for example, FFT analysis processing or the like on the collected data (each data of the Doppler signal SΔf1 and the Doppler signal SΔf2 corresponding to the collection time TH), thereby performing the Doppler frequency Δf1. And the phase φ1 and the Doppler frequency Δf2 and the phase φ2 are detected and provided to the high-speed speed distance calculation unit 62, respectively.

  The high-speed speed distance calculation unit 62 calculates the above-described equation (1) using the Doppler frequency Δf1 from the high-speed FFT unit 61 or the above-described equation using the Doppler frequency Δf2 from the high-speed FFT unit 61. (2) is calculated, and the calculation result is set as the relative speed Vh of the measuring object 3.

  The high-speed speed distance calculation unit 62 calculates the difference between the phase φ1 and the phase φ2 from the high-speed FFT unit 61, that is, the phase difference φ1-φ2, and uses the phase difference φ1-φ2 to calculate the above equation (3 ) And the calculation result is set as the distance Lh of the measuring object 3.

  Further, the high speed speed distance calculation unit 62 calculates the following equation (4) using the FFT analysis processing result by the high speed FFT unit 61, and sets the calculation result as the power Ph.

P = √ (R ² + I ² ) (4)
P represents power, R represents a real part, and I represents an imaginary part.

  That is, the square root of the sum of the square value of the real part R and the square value of the imaginary part R in the value obtained by the FFT analysis process is the electric power Ph.

  Then, the high speed speed distance calculation unit 62 generates and outputs a high speed measurement result Sh including the relative speed Vh, the distance Lh, and the power Ph.

  On the other hand, the low-speed measurement mode measurement processing unit 54 executes the measurement process once by using the data held in the data acquisition holding unit 52 for a time TL (for example, 450 msec) longer than the time TH. The resulting low speed measurement result S1 is output. Therefore, the low speed measurement mode measurement processing unit 54 is provided with a low speed FFT unit 71 and a low speed speed distance calculation unit 72.

  The low speed FFT unit 71 collects data held in the data acquisition holding unit 52 during the collection time TL. That is, the data acquisition and holding unit 52 performs the sampling time TL immediately before the Doppler signal SΔf1 having the Doppler frequency Δf1 and the Doppler signal SΔf2 having the Doppler frequency Δf2. The data acquired and held is collected by the low-speed FFT unit 71.

  Then, during the measurement processing time (calculation time) TC, the following measurement processing is executed by the low speed FFT unit 71 and the low speed speed distance calculation unit 72.

  That is, the low-speed FFT unit 71 performs, for example, FFT analysis processing or the like on the collected data (each data of the Doppler signal SΔf1 and the Doppler signal SΔf2 corresponding to the collection time TL), so that the Doppler frequency Δf1 And the phase φ1 and the Doppler frequency Δf2 and the phase φ2 are detected and provided to the low-speed speed distance calculation unit 72, respectively.

  The low speed speed distance calculation unit 72 calculates the above equation (1) using the Doppler frequency Δf1 from the low speed FFT unit 71 or the above equation using the Doppler frequency Δf2 from the low speed FFT unit 71. (2) is calculated, and the calculation result is set as the relative speed Vl of the measuring object 3.

  Further, the low speed speed distance calculation unit 72 calculates the difference between the phase φ1 and the phase φ2 from the low speed FFT unit 71, that is, the phase difference φ1-φ2, and uses the phase difference φ1-φ2 to calculate the above equation (3 ) And the calculation result is set as the distance Ll of the measuring object 3.

  Further, the low speed speed distance calculation unit 72 calculates the above-described equation (4) using the FFT analysis processing result by the low speed FFT unit 71, and sets the calculation result as the power Pl.

  Then, the low speed speed distance calculation unit 72 generates and outputs a low speed measurement result Sl including the relative speed Vl, the distance Ll, and the power Pl.

  As a result, the high-speed measurement result Sh from the high-speed speed distance calculation unit 62 and the low-speed measurement result Sl from the low-speed speed distance calculation unit 72 are input to the processing arithmetic device 2. In the processing arithmetic unit 2, the high-speed measurement result Sh is used when high-speed processing is desired, and the low-speed measurement result S1 is used when high-precision processing is desired.

  By the way, as described above, in the present invention, in order to remove the influence of interference caused by the vehicle surface shape or the like, focusing on the fact that the power fluctuation occurs along the time axis, Simultaneously with the calculation, calculation of the low speed measurement result S1 with an emphasis on accuracy is performed, and when the information of the measurement object 3 being tracked is lost due to a decrease in the SN ratio in the high speed measurement result Sh, the low speed measurement result S1 It is supposed to complement using.

  Here, the distance output (distance Lh) at the high speed measurement result Sh and the distance output (distance at the low speed measurement result Sl along the time axis (represented by the actual distance (m) on the horizontal axis in FIG. 8). L1) and the power ratio (power Ph) in the high-speed measurement result Sh and the power ratio (power Pl) in the low-speed measurement result S1 are drawn as shown in FIG.

  In FIG. 8, both the left and right axes are scaled on the vertical axis, but the right vertical axis indicates the distance output measured by the two-frequency CW radar 1, that is, the length (m) of the distance Lh and the distance Ll. The left vertical axis represents the power ratio measured by the two-frequency CW radar 1, that is, the magnitude (dB) of the power Ph and the power Pl. The values of the left and right vertical axes both increase from the bottom to the top in the figure. Further, the horizontal axis represents the actual distance (m) between the two-frequency CW radar 1 and the measurement object 3, and the distance between the two increases with increasing distance from the right to the left in the figure.

  That is, first, the distance output (distance Lh, distance Ll) on the upper side in the figure will be described. In these graphs, the actual distance (m) on the horizontal axis is the same as the distance output (m) on the right vertical axis. Ideally, the value should be proportional. However, the measurement result may differ from the actual distance, and the high-speed measurement mode has a feature that it has a high-speed response but a low accuracy compared to the low-speed measurement mode. The graph is more distant from the ideal proportional relationship than Ll.

  In addition, when interference between reflected waves on the multipath or the vehicle surface occurs, the waveform greatly fluctuates at the distance Lh included in the high-speed measurement result Sh. For example, the actual distance is 23 (m) (in the drawing) Despite being 23 (m) on the horizontal axis), the measured distance output is 9 (m) (near 9 (m) on the vertical axis in the figure) and 31 (m) (in the figure) It is a value far from the actual distance. On the other hand, the distance Ll included in the low-speed measurement result Sl is higher in accuracy than the distance Lh, and thus the distance Lh is not as far from the actual distance.

  At this time, the lower power ratio (power Ph, power Pl) in the figure is smaller as the actual distance from the measurement object 3 increases, but the power fluctuation increases when interference occurs ( Electric power around 23 (m) on the horizontal axis in the figure.

  As described above, when interference occurs, the distance output (distance Lh, distance Ll) and power ratio (power Ph, power Pl) take characteristic values. In this embodiment, attention is paid to these values. Thus, when interference occurs, the high-precision low-speed measurement result S1 is used instead of the low-precision high-speed measurement result Sh.

  The processing arithmetic device 2 has such a function.

  Specifically, in the processing operation device 2, the tracking processing is performed while performing the tracking processing based on the information (for example, the relative speed Vh, the distance Lh, etc.) obtained by the signal processing based on the high-speed measurement result Sh. When the measurement object 3 that has been suddenly no longer detected (for example, in the vicinity of 23 (m) on the horizontal axis where the distance Lh is steep in FIG. 8), the calculation result based on the low-speed measurement result S1 with high detection performance or By referring to the tracking result, tracking can be continued without losing sight of the measurement object 3.

  Further, in the processing operation device 2, while performing predetermined processing based on information (for example, relative speed Vh, distance Lh, etc.) obtained by signal processing based on the high-speed measurement processing Sh, the power Ph or the power Pl When the power is lower than the threshold (for example, around 23 (m) on the horizontal axis where the power fluctuation increases in FIG. 8), it is based on the low-speed measurement result S1 with high detection performance. By referring to the calculation result, it is possible to reliably obtain information on the measurement object 3.

  Hereinafter, in the processing operation device 2, the former operation is referred to as a first processing operation mode, and the latter operation is referred to as a second processing operation mode.

  A detailed configuration of the processing arithmetic device 2 that operates in the first processing arithmetic mode and the second processing arithmetic mode will be described with reference to the block diagram of FIG.

  The processing operation device 2 in the example of FIG. 9 is configured to include a high-speed tracking processing unit 81 through a post-processing unit 87.

  The high-speed measurement result Sh and the low-speed measurement result S1 are input to the processing arithmetic device 2 from the two-frequency CW radar 1. The processing operation device 2 executes processing using the high-speed measurement result Sh when executing high-speed processing, and executes processing using the low-speed measurement result S1 when executing high-precision processing.

  When the processing operation device 2 operates in the first processing operation mode, the high-speed tracking processing unit 81, the low-speed tracking processing unit 82, the tracking unit 83, and the risk determination process among the high-speed tracking processing unit 81 to the post-processing unit 87. The function is realized by the unit 86. However, description of each block which implement | achieves 1st process calculation mode is abbreviate | omitted here, and it will also be demonstrated, when demonstrating operation | movement of the process calculation apparatus 2 in FIG. 10 thru | or FIG. 13 mentioned later.

  Further, when the processing arithmetic device 2 operates in the second processing arithmetic mode, the high-speed tracking processing unit 81, the low-speed tracking processing unit 82, the power value determination unit 84, among the high-speed tracking processing unit 81 to the post-processing unit 87, The function is realized by the switch unit 85 and the post-processing unit 87. However, description of each block which implement | achieves 2nd process calculation mode is abbreviate | omitted here, and it will also be demonstrated, when describing operation | movement of the process calculation apparatus 2 in FIG. 14 mentioned later.

  Next, an operation example of the processing arithmetic device 2 in FIG. 9 will be described with reference to the flowcharts in FIGS. 10 to 14.

  First, the processing arithmetic device 2 that operates in the first processing arithmetic mode will be described with reference to the flowcharts of FIGS. 10 to 13.

  FIG. 10 is a flowchart for describing high-speed tracking processing executed by the high-speed tracking processing unit 81.

  In step S11, the high-speed tracking processing unit 81 searches for the high-speed measurement result Sh output from the two-frequency CW radar 1, and if it is determined in step S12 that the high-speed measurement result Sh has been detected, the process proceeds to step S13. Proceed to On the other hand, when it is determined in step S12 that the high speed measurement result Sh has not been detected, the process of detecting the high speed measurement result Sh is repeated.

  In step S13, the high-speed tracking processing unit 81 extracts the target (measurement object 3) of the detected high-speed measurement result Sh. In steps S14 and S15, the extracted target relative speed Vh and the distance Lh are obtained. To detect. Then, in step S16, the above-described processing in steps S12 to S16 is repeated until it is determined that the search for the high-speed measurement result Sh has been completed.

  That is, the relative speed Vh of the measurement object 3 and the distance Lh measured by the two-frequency CW radar 1 are detected by repeating the processes of steps S12 to S16.

  Subsequently, when it is determined in step S16 that the search for the high-speed measurement result Sh has been completed, the high-speed tracking processing unit 81 obtains the tracking history of the measurement object 3 being tracked from the tracking unit 83 in step S17. The recorded tracking history is acquired, and in step S18, the detection target (the measurement target 3 having the detected relative speed Vh and the distance Lh) is detected in the detection target (within the detection range). It is determined whether it corresponds to the measurement object 3) already existing and measured.

  When it is determined in step S18 that the detection target corresponds to the already detected object, the high speed tracking processing unit 81 associates the detection target with the ID of the already detected object, while the detection target becomes the already detected object. If it is determined that it does not correspond, a new ID is associated with the detection target. Then, in step S21, the above-described steps S12 to S21 are performed until it is determined that the ID association has been completed for all the detected objects except for the detected objects that have moved out of the detection range. The process is repeated.

  That is, by repeating the processing from step S12 to step S21, IDs are associated with all already detected objects within the detection range, and new IDs are also obtained for newly detected objects to be measured. Is granted.

  In step S21, when it is determined that the ID association has been completed for all of the detected objects except for the detected object that has moved out of the detection range, in step S22, the high-speed tracking processing unit 81 outputs the high-speed processing result to the tracking unit 83. Here, the high-speed processing result includes the relative speed Vh and the distance Lh associated with each of the ID associated with the detected object and the ID assigned to the newly detected measurement object. ing.

  Thereafter, the process returns to step S11, and the above-described process is repeated.

  As described above, the high-speed tracking processing unit 81 excludes a known object that has moved out of the detection range from the high-speed measurement result Sh that is sequentially output from the two-frequency CW radar 1 at a timing faster than the low-speed measurement result S1. IDs for all measurement objects are assigned, and new IDs are assigned to measurement objects that have newly moved within the detection range, and these IDs are associated with relative speed Vh and distance Lh. Output high-speed processing results as data.

  Next, the low speed tracking process executed by the low speed tracking processing unit 82 will be described with reference to the flowchart of FIG.

  Note that the processing performed by the low-speed tracking processing unit 82 is basically the same as the processing performed by the high-speed tracking processing unit 81, and therefore description thereof will be omitted as appropriate. That is, in the low-speed tracking processing unit 82, as compared with the high-speed tracking processing unit 81, the low-speed measurement result Sl is input instead of the high-speed measurement result Sh, and the low-speed measurement result Sl is processed. The difference is that the process of associating the measurement object with the ID (the process of steps S18 to S21 in FIG. 10) is not performed.

  Therefore, the processes in steps S31 to S37 in FIG. 11 correspond to the processes in steps S11 to S16 and step S22 in FIG.

  That is, the low-speed tracking processing unit 82 outputs the low-speed processing result to the tracking unit 83 by performing the processing from step S31 to step S37 in FIG. Here, the low speed processing result includes the relative speed Vl and the distance Ll of the measurement object.

  As described above, in the low-speed tracking processing unit 82, the relative velocity Vl and the distance Ll of the measurement object are obtained from the low-speed measurement result S1 sequentially output from the two-frequency CW radar 1 at a timing later than the high-speed measurement result Sh. Outputs the low-speed processing result as included data.

  The processing for calculating the high-speed processing result in the high-speed tracking processing unit 81 and the processing for calculating the low-speed processing result in the low-speed tracking processing unit 82 are performed independently and in parallel. The high-speed processing result from the processing unit 81 and the low-speed processing result from the low-speed tracking processing unit 82 are sequentially input.

  FIG. 12 is a flowchart for explaining the tracking process executed by the tracking unit 83.

  In step S <b> 51, the tracking unit 83 performs a tracking process of the measurement object existing in the detection range based on the high-speed processing result supplied from the high-speed tracking processing unit 81. That is, since the ID of the measurement object, the relative speed Vh and the distance Lh are stored in association with each other in the high-speed processing result, the measurement object sequentially input from the high-speed tracking processing unit 81 by the tracking unit 83. For each ID, a tracking process based on the relative speed Vh and the distance Lh is performed.

  In step S <b> 52, the tracking unit 83 determines whether or not the measurement object being tracked is lost. That is, if the tracking process is performed for each measurement object ID, the measurement object being tracked may be lost at some time. As described above, this is due to the fact that the information on the measurement object being tracked is lost due to power fluctuations caused by interference due to multipath or the like.

  Specifically, as described above, for example, in the high-speed tracking processing unit 81, an ID is assigned to each measurement object. However, when power fluctuation occurs, this is the cause, and originally corresponds to the already detected object. As a result, a new ID may be erroneously assigned to a detection target that must be associated with an ID of an already detected object. For example, in the high-speed tracking processing unit 81, when the change in the distance Lh is steep even though the relative speed Vh is the same (for example, around 23 (m) on the horizontal axis where the distance Lh is steep in FIG. 8 described above. ), It is determined that it is not a detected object but a measurement object that has moved anew (the processing from step S18 to step S20 in FIG. 10).

  Then, the tracking unit 83 tracks a certain measurement object according to the measurement object ID included in the high-speed processing results that are sequentially sent. However, the measurement object ID corresponding to the measurement object is suddenly determined. It will not be sent and you will lose sight of the measurement object.

  If it is determined in step S52 that the measurement object has been lost, in step S53, the tracking unit 83 refers to the low speed processing result instead of the high speed processing result. Specifically, for example, the tracking unit 83 erroneously assigns the lost measurement object based on the tracking history by referring to the relative speed Vl and the distance Ll instead of the relative speed Vh and the distance Lh. Instead of the new ID, the detected object ID that should be associated with the measurement object is given.

  In other words, the high-speed processing result from the high-speed tracking processing unit 81 and the low-speed processing result from the low-speed tracking processing unit 82 are sequentially input to the tracking unit 83, but the low-speed processing result is compared with the high-speed processing result. Since it takes a long time, it has a characteristic that it is a low-speed response but is highly accurate. Therefore, by using this low-speed processing result, although there is a delay in response time, the probability that the data will be composed only of signals with minimal power is reduced, and the resolution is generally increased. That is, the detection performance of the measurement object is improved.

  In step S55, the tracking unit 83 outputs the tracking result to the risk determination processing unit 86, the process returns to step S51, and the above-described processing is repeated. That is, when it is determined in step S52 that the measurement object that has been lost is detected again, the tracking unit 83 refers to the high-speed processing result again instead of the low-speed processing result in step S54, and in step S55. The tracking result based on the high-speed processing result is output.

  As described above, for example, in the case of performing tracking processing based on the result of high-speed processing obtained in normal (high-speed measurement mode) signal processing, when the measurement object suddenly becomes undetectable, the detection performance is improved. By referring to the low-speed processing result of the high low-speed measurement mode, it is possible to continue tracking without losing sight of the measurement object. Moreover, if a measurement object can be detected by a normal process, it can be tracked again at a normal response speed.

  Then, the tracking result from the tracking unit 83 is sequentially input to the risk determination processing unit 86.

  FIG. 13 is a flowchart illustrating the risk determination process executed by the risk determination processing unit 86.

  The risk determination processing unit 86 acquires the tracking result from the tracking unit 83 in step S71, performs a predetermined analysis process on the tracking result in step S72, and performs measurement based on the analysis result in step S73. It is determined whether it can be determined that the object is dangerous from the movement route of the object.

  If it is determined in step S73 that the analysis results in danger, for example, a signal for instructing the driver to present danger or to perform safe operation is output. Thereby, the vehicle-mounted apparatus which detected this signal performs the process which shows danger with respect to a driver, for example. On the other hand, if it is determined in step S73 that the analysis result is safe, the process of step S74 is skipped, the process returns to step S71, and the processes of steps S71 to S74 described above are repeated.

  Thus, for example, in a system that executes a process that requires a high-speed response, for example, a pre-crash system that performs a process of detecting that a measurement object is likely to collide with itself (pre-crash), Even when interference between reflected waves occurs, the tracking of the measurement object can be continued using high-accuracy data, so that it is possible to present the danger to the driver more reliably.

  As described above, the processing operation device 2 operates in the first processing operation mode.

  Next, the processing arithmetic device 2 that operates in the second processing arithmetic mode will be described with reference to the flowchart of FIG.

  In the processing arithmetic device 2 operating in the second processing arithmetic mode, the processing executed by the high-speed tracking processing unit 81 and the low-speed tracking processing unit 82 is basically the same as in the case of operating in the first processing arithmetic mode. It is. That is, as described above with reference to the flowcharts of FIGS. 10 and 11, the high-speed processing result from the high-speed tracking processing unit 81 and the low-speed processing result from the low-speed tracking processing unit 82 are input to the switch unit 85. .

  That is, the switch unit 85 switches the input destination from one of the high speed tracking processing unit 81 and the low speed tracking processing unit 82 based on the control of the power value determination unit 84. That is, the power value determination unit 84 monitors the power Ph included in the high-speed measurement result Sh from the two-frequency CW radar 1 or the power Pl included in the low-speed measurement result Sl, and according to the monitoring result, the switch unit 85 Controls the switching operation.

  FIG. 14 is a flowchart illustrating the power value determination process executed by the power value determination unit 84.

  The power value determination unit 84 detects the power Ph or the power Pl from the high speed measurement result Sh or the low speed measurement result S1 output from the two-frequency CW radar 1 in step S91, and in step S92, the power (power Ph). , Power Pl) and a predetermined threshold.

  When it is determined in step S92 that the power exceeds the threshold, in step S93, the power value determination unit 84 switches the switch unit so that the high-speed processing result from the high-speed tracking processing unit 81 is output to the subsequent-stage processing unit 87. 85 is switched. On the other hand, if it is determined in step S92 that the power is below the threshold value, in step S94, the power value determination unit 84 outputs the low speed processing result from the low speed tracking processing unit 82 to the subsequent processing unit 87. The switch unit 85 is switched.

  That is, for example, when a predetermined process is performed based on the high-speed processing result from the power value determination unit 84 in the subsequent stage processing unit 87, interference occurs due to the vehicle surface shape, the multipath of the road surface, and the like. If a phenomenon in which the power fluctuates significantly occurs (in FIG. 8, near 23 (m) on the horizontal axis where the power fluctuation increases), the power value determination unit 84 determines that the power is below the threshold value. The low-speed processing result based on the low-speed measurement result S1 with high detection performance is output. As a result, the post-processing unit 87 can reliably obtain accurate information about the measurement object.

  As described above, the processing operation device 2 operates in the second processing operation mode.

  Note that the processing operation device 2 in FIG. 9 includes a high-speed tracking processing unit 81 to a subsequent processing unit 87 in order to explain both the first processing operation mode and the second processing operation mode. As described above, the processing arithmetic device 2 that executes only the first processing arithmetic mode or the first processing arithmetic mode only needs to have a block for realizing the mode. That is, the processing operation device 2 that executes only the first processing operation mode includes a high-speed tracking processing unit 81, a low-speed tracking processing unit 82, a tracking unit 83, and a danger determination processing unit 86. On the other hand, the processing arithmetic device 2 that executes only the second processing arithmetic mode includes a high-speed tracking processing unit 81, a low-speed tracking processing unit 82, a power value determination unit 84, a switch unit 85, and a post-processing unit 87.

  As described above, if radar signal processing (low-speed mode) using a time longer than the normal sampling time is performed simultaneously with the normal radar signal processing, the delay in response time is reduced by increasing the sampling time. Although it occurs, the probability that the data is composed only of the signal whose power is minimized is reduced, and the resolution is generally increased. That is, the detection performance of the measurement object is also improved, and the same effect can be obtained by the tracking process using the output.

  In addition, for example, in the case of tracking processing based on the result of high-speed processing obtained in normal (high-speed measurement mode) signal processing, when a measurement object cannot be detected suddenly, low-speed measurement with high detection performance By referring to the calculation result or the tracking result of the mode, it is possible to keep tracking without losing sight of the measurement object. Moreover, if a measurement object can be detected by a normal process, it can be tracked again at a normal response speed.

  By the way, the above-described configuration of the present invention can be applied not only to the system having the configuration shown in FIGS. 4 and 5, but also to various configurations of apparatuses and systems.

  In addition, a system represents the whole apparatus comprised by a some processing apparatus and a process part here. In other words, the system shown in FIG. 5 can be regarded as one measuring apparatus 101 as shown in FIG. That is, the measurement apparatus 101 in the example of FIG. 15 includes a two-frequency CW radar unit 111 as one processing unit corresponding to the two-frequency CW radar 1 and a processing calculation unit 112 as one processing unit corresponding to the processing calculation device 2. It is one apparatus which consists of.

  In the above-described example, the two-frequency CW radar 1 measures only the relative speed v and the distance L of the measurement object 3, but measures another physical quantity, for example, the angle of the measurement object 3. May be. The angle measurement method in this case is also not particularly limited. For example, by configuring the reception antenna unit 16 in FIG. 5 with two antennas, the amplitude ratio of the sum and difference of the reception signals of these two antennas. It is also possible to employ a method of calculating the angle using the so-called monopulse method.

  Furthermore, the FFT analysis processing performed by the high-speed measurement mode measurement processing unit 53 and the low-speed measurement mode measurement processing unit 54 of the calculation processing unit 24 of FIG. 7 can be performed on the processing calculation unit 2 side. In that case, for example, the high-speed tracking processing unit 81 of FIG. 9 executes the measurement process using the data held in the calculation control unit 24 for a time TH (for example, 50 msec) once, and the high-speed measurement result Sh Is obtained. Similarly, the low-speed tracking processing unit 82 in FIG. 9 executes a measurement process using data held in the data acquisition holding unit 52 for a time TL (for example, 450 msec), and obtains a low-speed measurement result S1. It is done.

  By the way, the above-described series of processes (or a part of them) can be executed by hardware, but can also be executed by software.

  In this case, the apparatus (system defined above) for executing the series of processes or a part thereof can be configured by a computer as shown in FIG. 16, for example.

  In FIG. 16, a CPU (Central Processing Unit) 201 executes various processes according to a program recorded in a ROM (Read Only Memory) 202 or a program loaded from a storage unit 208 to a RAM (Random Access Memory) 203. To do. The RAM 203 also appropriately stores data necessary for the CPU 201 to execute various processes.

  The CPU 201, ROM 202, and RAM 203 are connected to each other via a bus 204. An input / output interface 205 is also connected to the bus 204.

  The input / output interface 205 includes an input unit 206 such as a keyboard and a mouse, an output unit 207 including a display, a storage unit 208 including a hard disk, and a communication unit 209 including a modem and a terminal adapter. It is connected. The communication unit 209 performs communication processing with other devices via a network including the Internet. Furthermore, the communication unit 209 performs transmission / reception processing of the transmission signal Ss and the reception signal Sr for measuring the measurement object 3 as shown in FIG.

  A drive 210 is also connected to the input / output interface 205 as necessary, and a removable medium 211 such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory is appropriately installed, and a computer program read from them is loaded. Installed in the storage unit 208 as necessary.

  When a series of processing is executed by software, a program constituting the software executes various functions by installing a computer incorporated in dedicated hardware or various programs. For example, a general-purpose personal computer is installed from a network or a recording medium.

  As shown in FIG. 16, the recording medium containing such a program is distributed to provide a program to the user separately from the apparatus main body, and a magnetic disk (including a floppy disk) on which the program is recorded. Removable media (package media) consisting of optical disks (including CD-ROM (compact disk-read only memory), DVD (digital versatile disk)), magneto-optical disks (including MD (mini-disk)), or semiconductor memory ) 211, but also includes a ROM 202 in which a program is recorded and a hard disk included in the storage unit 208 provided to the user in a state of being incorporated in the apparatus main body in advance.

  In the present specification, the step of describing the program stored in the recording medium is not limited to the processing performed in chronological order according to the described order, but is not necessarily performed in chronological order. It also includes processes that are executed individually.

  Further, in this specification, the system represents the entire apparatus constituted by a plurality of apparatuses.

  Furthermore, the embodiments of the present invention are not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention.

It is a figure explaining the interference by a received signal. It is a wave form diagram of a received signal. It is a figure which shows the electric power conversion value of a received signal. It is a block diagram which shows the structural example of the measurement system to which this invention is applied. It is a block diagram which shows the detailed structural example of the 2 frequency CW radar of FIG. It is a figure explaining an example of the isolation | separation method of the Doppler signal which has two Doppler frequencies (DELTA) f1 and (DELTA) f2. It is a block diagram which shows the detailed structural example of the calculation control part of FIG. It is the graph which compared the high-speed measurement result and the low-speed measurement result about distance and power ratio. It is a block diagram which shows the detailed structural example of a processing arithmetic unit. It is a flowchart explaining a high-speed tracking process. It is a flowchart explaining a low-speed tracking process. It is a flowchart explaining a tracking process. It is a flowchart explaining a danger determination process. It is a flowchart explaining an electric power value determination process. It is a block diagram which shows the structural example of the measuring apparatus with which this invention is applied. It is a block diagram which shows another example of the structure of all or one part of the measurement system and measurement apparatus to which this invention is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 2 frequency CW radar 2 Processing arithmetic unit 3 Measurement object 11 Oscillation part 12 Amplification part 13 Branch part 14 Amplification part 15 Antenna part 16 Antenna part 17 Amplification part 18 Mixing part 19 Switching timing part 20 Switch part 21-1, 21- 2 Amplifying section 22-1, 22-2 Low pass filter 23 A / D conversion section 24 Operation control section 51 Control section 52 Data acquisition holding section 53 High speed measurement mode measurement processing section 54 Low speed measurement mode measurement processing section 61 High speed FFT section 62 High speed Speed distance calculation unit 71 Low speed FFT unit 72 Low speed speed distance calculation unit 81 High speed tracking processing unit 82 Low speed tracking processing unit 83 Tracking unit 84 Power value determination unit 85 Switch unit 86 Risk determination processing unit 87 Subsequent processing unit 101 Measuring device 111 Two frequencies CW radar unit 112 Processing operation unit 201 CPU
202 ROM
203 RAM
204 Bus 205 Input / Output Interface 206 Input Unit 207 Output Unit 208 Storage Unit 209 Communication Unit 210 Drive 211 Removable Media

Claims (6)

In a measuring apparatus for measuring the object by a Doppler method using a Doppler signal for a reflected signal at an object of a transmission signal,
As a measurement mode for performing frequency analysis on the collected data collected from the reflected signal and measuring the object by the Doppler method using the frequency analysis result, the collection time for acquiring the collected data from the reflected signal A first measurement mode that is a first time and a second measurement mode that is a second time in which the collection time is longer than the first time;
First measurement processing means for executing measurement processing in the first measurement mode;
Second measurement processing means for executing measurement processing in the second measurement mode;
Processing arithmetic means for executing predetermined processing using the first measurement result in the first measurement mode,
The measurement process in the first measurement mode and the measurement process in the second measurement mode are performed independently and in parallel.
When it is determined that interference of the reflected signal has occurred, the processing calculation unit executes a predetermined process using the second measurement result in the second measurement mode instead of the first measurement result. measuring device. The said process calculating means performs a predetermined process using the said 1st measurement result instead of the said 2nd measurement result, when it is judged that the convergence of the said reflected signal generate | occur | produced. measuring device. The processing calculation means performs the tracking process of the object using the first measurement result, and when the tracking of the object that has been tracked becomes impossible, the process is not performed instead of the first measurement result. The measurement apparatus according to claim 1, wherein tracking processing is performed using the second measurement result. The processing calculation means performs a tracking process of the object based on the measured relative speed and distance of the object, and the first measurement result is obtained when a change width of the distance is larger than a predetermined threshold. The measurement apparatus according to claim 3, wherein a tracking process is performed using the second measurement result instead of the measurement result. The said process calculating means performs a predetermined | prescribed process using the said 2nd measurement result instead of a said 1st measurement result, when the electric power of the said reflected signal is less than a predetermined threshold value. Measuring device. In the measuring method of the measuring apparatus for measuring the object by the Doppler method using the Doppler signal for the reflected signal at the object of the transmission signal,
As a measurement mode for performing frequency analysis on the collected data collected from the reflected signal and measuring the object by the Doppler method using the frequency analysis result, the collection time for acquiring the collected data from the reflected signal A first measurement mode that is a first time, and a second measurement mode that is a second time in which the collection time is longer than the first time;
Performing a measurement process in the first measurement mode;
Performing the measurement process of the second measurement mode;
Performing a predetermined process using the first measurement result in the first measurement mode,
The measurement process in the first measurement mode and the measurement process in the second measurement mode are performed independently and in parallel.
A measurement method that executes predetermined processing using a second measurement result in the second measurement mode instead of the first measurement result when it is determined that interference of the reflected signal has occurred.

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