JP4999586B2 - Radar equipment - Google Patents

Description

  The present invention provides a radar device that receives a pulse signal reflected by a target, detects a phase value at two points in the received pulse, and obtains a phase difference between the two, thereby detecting a target Doppler velocity with one pulse. It is about.

  Conventionally, a Doppler weather radar apparatus is known as an apparatus for observing weather conditions such as rain and clouds by transmitting and receiving radio waves. In this type of radar device, a plurality of pulse signals are emitted toward a target such as rain or clouds to be observed, and a pulse signal that is reflected by the target is received. The dynamic change of the target is observed by calculating the Doppler velocity from the Doppler frequency.

  A pulse pair method is well known as a method for calculating the Doppler velocity from the received pulse signal. In this pulse pair method, a Doppler velocity is obtained by obtaining a phase value with respect to a received pulse signal at a cycle of a pulse repetition time and detecting a phase change amount of two adjacent pulses. The pulse pair method does not need to convert a time signal into a frequency domain signal unlike the Fourier transform, and real-time signal processing in the time domain is possible. The Doppler speed can be calculated (see, for example, Non-Patent Document 1 and Patent Document 1).

  Further, in generating a pulse signal, a magnetron oscillator that can be easily manufactured is often used in order to manufacture a high-power pulse signal generator at low cost (for example, see Patent Document 1).

Japanese Patent Laid-Open No. 11-183616 Edited by Meteorological Research Institute, “Meteorological Research Institute Technical Report No. 19, Research on Meteorology and Sea Conditions by Doppler Radar”, Meteorological Research Institute, March 31, 1986, P10-13

  However, in the conventional radar apparatus, as described above, in order to obtain the target Doppler velocity, the phase difference must be detected from the mutual phase value using two pulses of the received pulse signal, and The phase value must be calculated every pulse repetition time. For this reason, if the pulse repetition time of the actual pulse signal varies due to instability of the operation of the magnetron oscillator, or if the initial phase of the pulse signal varies and the phase varies from pulse to pulse, It is not clear whether the phase difference detected by the two adjacent pulses is generated corresponding to the time difference between the two points from which the phase was obtained. Further, when the phase of two adjacent pulses cannot be detected, the Doppler velocity cannot be measured. Therefore, as a result of calculating the Doppler speed with data in which the phase difference and the time difference are not taken into account, there are problems that an error occurs and the detection of the Doppler speed is lost.

  The present invention has been made in order to solve the above-described problems. The purpose of the present invention is to determine the phase of two points in one pulse even if there are fluctuations in pulse repetition time and fluctuations in phase for each pulse. Thus, a radar apparatus capable of detecting the target Doppler velocity is obtained by obtaining the phase difference between them.

A radar apparatus according to the present invention includes a pulse specification setting unit that sets specifications of a transmission pulse signal, a pulse waveform generation unit that generates a pulse signal based on specifications set by the pulse specification setting unit, Using the pulse signal generated by the pulse waveform generator as a modulation signal, a transmitter that generates a transmission signal by pulse-modulating a high-frequency signal, a circulator that switches the path between the transmission signal and the reception signal, and directing the transmission signal to the target The antenna unit receives the signal reflected by the target, receives the signal received by the antenna unit, converts the received signal into a low-frequency pulse signal, and the pulse signal frequency-converted by the receiver unit. An A / D converter for digitally converting the signal and a pulse signal digitally converted by the A / D converter by the pulse specification setting unit. Based on the set specifications, a pulse signal analyzer that detects two points of time in one pulse, a phase detector that detects phase values at two points of time detected by the pulse signal analyzer, And a Doppler speed calculation unit that calculates the target Doppler speed based on the phase value detected by the phase detection unit and the wavelength of the transmission signal obtained from the transmission unit .

  The radar apparatus according to the present invention detects the phase of two points in one pulse and obtains the phase difference between them by detecting the phase difference even if there is a fluctuation in pulse repetition time or a phase fluctuation for each pulse. There is an effect that the Doppler speed can be detected.

Embodiment 1 FIG.
A radar apparatus according to Embodiment 1 of the present invention will be described with reference to FIGS. 1 is a block diagram showing a configuration of a radar apparatus according to Embodiment 1 of the present invention. In the following, in each figure, the same reference numerals indicate the same or corresponding parts.

  1, a radar apparatus according to Embodiment 1 of the present invention includes a pulse specification setting unit 1, a pulse waveform generation unit 2, a transmission unit 3, a circulator 4, an antenna unit 5, and a reception unit 6. The A / D conversion unit 7, the pulse signal analysis unit 8, the phase detection unit 9, and the Doppler velocity calculation unit 10 are provided.

  Next, the operation of the radar apparatus according to the first embodiment will be described with reference to the drawings. 2 and 3 are timing charts showing how two times of received pulse signals are detected by the radar apparatus according to Embodiment 1 of the present invention.

  First, the pulse specification setting unit 1 has a function of setting a pulse width and a pulse repetition time as specifications of a pulse signal to be transmitted. Information on the pulse specifications is output from the pulse specification setting unit 1 to the pulse waveform generation unit 2 of the next stage and the pulse signal analysis unit 8 of the reception system.

  The pulse waveform generation unit 2 has a function of generating a pulse signal based on information on the specification of the transmission pulse signal output from the pulse specification setting unit 1. This pulse signal is a rectangular pulse train, and is used as a modulation signal for pulse-modulating the transmission signal.

  The transmission unit 3 has a function of generating a high-frequency pulse signal in the gigahertz band based on the pulse specifications of the pulse train input from the pulse waveform generation unit 2, and outputs the generated high-frequency pulse signal as a transmission signal. The transmission signal is obtained by pulse-modulating a high-frequency signal using a rectangular pulse signal input from the pulse waveform generation unit 2 as a modulation signal. In the process of generating the high frequency signal, the wavelength λ of the transmission signal is determined, and the transmission unit 3 outputs information on the wavelength λ of the transmission signal to the Doppler velocity calculation unit 10.

  The circulator 4 has a function of outputting a transmission signal from the transmission unit 3 to the antenna unit 5 and outputting a reception signal from the antenna unit 5 to the reception unit 6.

  The antenna unit 5 has a function of radiating the transmission signal output from the transmission unit 3 to the space and receiving the reflected radio wave that has arrived after the transmission signal radiated toward the target is reflected by the target as a reception signal. Have.

  The reception unit 6 has a function of inputting the reception signal received by the antenna unit 5 and performing frequency conversion from a high frequency pulse signal in the gigahertz band to a pulse signal in the low frequency band (several tens to several hundreds of megahertz). In addition, even when a transmission signal output from the transmission unit 3 is input, it has a function of performing frequency conversion from a high frequency pulse signal in the gigahertz band to a pulse signal in the low frequency band (several tens to several hundreds of megahertz).

  The A / D converter 7 has a function of analog / digital conversion of the signal output from the receiver 6 at high speed.

  The pulse signal analysis unit 8 has a function of detecting time at two points in one pulse with respect to the digitized reception signal output from the A / D conversion unit 7.

FIG. 2 shows a situation where two time points are detected. In FIG. 2, the voltage envelope of the received pulse signal is compared with a preset threshold value to obtain a point that intersects the threshold value. When the time difference between two adjacent points of the intersecting point is obtained, a value substantially matching the pulse width appears. If this value is smaller than the value T set based on the pulse width information output from the pulse specification setting unit 1, it is determined that the two points crossing the threshold value are within the pulse. , Output the corresponding two points of time respectively. That is, as shown in FIG. 2B, Δt (= t ₂ −t ₁ ) is smaller than the value T set based on the pulse width information output from the pulse specification setting unit 1. For example, it is determined that the points t ₁ and t ₂ are inside the pulse. The received signal used for analysis is also output.

As an example, FIG. 3 shows an example in which when a received signal is a pulse signal having a pulse width of 1 μs and a pulse repetition time of 1 ms, two points in the pulse are detected by comparison with a time T = 2 us that is twice the pulse width. It is.
(1) Since Δt ₁ <T, the points t ₁ and t ₂ are in the pulse. Therefore, t ₁ and t ₂ are output.
(2) Since Δt ₂ > T, nothing is done.
(3) Since Δt ₃ <T, the points at t ₃ and t ₄ are in the pulse. Therefore, t ₃ and t ₄ are output.
(4) Since Δt ₄ > T, nothing is done.
(5) Since Δt ₅ <T, the points t ₅ and t ₆ are in the pulse. _Thus, the output _t 5, t _6.

The phase detection unit 9 has a function of detecting the phase of the time from the two points of time detected by the pulse signal analysis unit 8. If the time of two points that are output from the pulse signal analysis unit 8 is t ₁ and t _2, the phase value theta ₂ in the phase value theta _1, and time t ₂ at time t _1, the pulse signal received complex voltage _z 1 ₌ x 1 + jy ₁ at time _{t 1,} and, by using a complex voltage _z 2 ₌ x 2 + jy ₂ at time _{t 2, the} can be calculated by equation (1) and (2).

Phase detector 9 outputs a phase value obtained by the formula (1) and (2), the time t ₁ and time t ₂ which obtains a phase value.

The Doppler velocity calculation unit 10 has a function of calculating a target Doppler velocity using the phase values and times at two points in one pulse output from the phase detection unit 9. The phase difference Δθ between time t ₁ and time t ₂ is obtained by equation (3).

  Further, the time difference Δt is obtained by the equation (4) from the difference in time between each other.

The Doppler frequency f _d is calculated by the equation (5) using the phase difference Δθ and the time difference Δt obtained by the equations (3) and (4).

Finally, the Doppler velocity v _d is calculated by the equation (6) from the Doppler frequency f _d and the wavelength λ of the transmission signal.

That is, the Doppler velocity calculation unit 10 calculates the Doppler frequency f _d based on the phase value detected by the phase detection unit 9, and based on the wavelength λ and the Doppler frequency f _d of the transmission signal obtained from the transmission unit 3, A target Doppler speed v _d is calculated.

  As described above, according to the first embodiment, since the time difference and the phase difference can be obtained from the time and phase of two points in one pulse of the received pulse signal, the pulse repetition time varies. Even if this occurs or the phase fluctuates for each pulse, the target Doppler speed can be detected without affecting the way the phase advances within the pulse. .

Embodiment 2. FIG.
A radar apparatus according to Embodiment 2 of the present invention will be described with reference to FIGS. FIG. 4 is a block diagram showing the configuration of the radar apparatus according to Embodiment 2 of the present invention.

  4, a radar apparatus according to Embodiment 2 of the present invention includes a pulse specification setting unit 1, a pulse waveform generation unit 2, a transmission unit 3, a circulator 4, an antenna unit 5, and a reception unit 6. A receiving unit (second receiving unit) 6A, an A / D converting unit 7, an A / D converting unit (second A / D converting unit) 7A, a pulse signal analyzing unit 8, and a pulse signal analyzing unit. A (second pulse signal analysis unit) 8A, a phase detection unit 9, a phase detection unit (second phase detection unit) 9A, a phase correction unit 11, and a Doppler velocity calculation unit 10 are provided.

  Next, the operation of the radar apparatus according to the second embodiment will be described with reference to the drawings.

  FIG. 5 is a timing chart showing one pulse signal of the reception signal and the transmission signal of the radar apparatus according to Embodiment 2 of the present invention. In FIG. 5, (a) represents one pulse signal of the reception signal, (b) represents one pulse signal of the transmission signal, and (c) represents one pulse signal of the transmission signal after correction.

FIG. 6 is a timing chart showing the phase relationship between the transmission signal and the reception signal of the radar apparatus according to Embodiment 2 of the present invention. In FIG. 6, the transmission signal and the reception signal are slid so that the phase at time t ₁ becomes zero (0) as shown in (b) from the relationship of (a). Next, as shown in (c), the phase at time t ₂ of the transmission signal is corrected to be zero (0).

  In the first embodiment, the phase value obtained from the received signal is directly used. In the second embodiment, the phase value detected in one pulse of the transmission signal, which does not include the Doppler frequency, is used as the reference phase value, and the two phases detected in one pulse of the reception signal are corrected. An example of this case will be described.

  Two phase values in one pulse of the received signal are input to the phase correction unit 11, and the phase of two points in one pulse is also processed for the transmission signal by the same processing as that for the received signal. A value is entered.

  That is, the receiving unit 6A frequency-converts the transmission signal generated by the transmitting unit 3 into a low-frequency pulse signal, and the A / D conversion unit 7A digitally converts the pulse signal frequency-converted by the receiving unit 6A. The pulse signal analysis unit 8A detects the time of two points within one pulse based on the parameters set by the pulse parameter setting unit 1 for the pulse signal digitally converted by the A / D conversion unit 7A. To do. The phase detector 9A detects phase values at two points of time detected by the pulse signal analyzer 8A.

  The time difference between two points of one pulse of the received signal shown in FIG. 5A and the time difference of two points within one pulse of the transmission signal shown in FIG. As shown in FIG. 5C, the two points on the transmission signal side are finely adjusted. It is convenient that the time difference between the two points on the transmission signal side is equal to or greater than the time difference between the two points on the reception signal side because the point on the transmission signal side is surely finely adjusted within the pulse. Since the transmission signal does not include the Doppler frequency, any pulse may be used as the pulse defining the two points.

The phase correction unit 11 corrects two phase values of the received signal as shown in FIG. First, of the two points of the transmission signal and the reception signal, the phase values of the transmission signal and the reception signal are slid so that the phase value at the earlier point (time t _{1 in} FIG. 6) becomes zero. Next, a correction amount at which the phase value on the transmission signal side becomes 0 at a later point of time (t _{2 in} FIG. 6) is detected, and the phase value on the reception signal side is corrected by the detected correction amount. By this operation, the later phase value is corrected to an absolute phase value with reference to 0.

  That is, the phase correction unit 11 corrects the phase value detected by the phase detection unit 9 with reference to the phase value detected by the phase detection unit 9A. Then, the Doppler velocity calculation unit 10 calculates a target Doppler velocity based on the phase value corrected by the phase correction unit 11 and the wavelength of the transmission signal obtained from the pulse waveform generation unit 2.

  As described above, according to the second embodiment, the phase of two points in one pulse of the reception signal can be corrected with reference to the phase value of the transmission signal that does not include the Doppler frequency. Thus, the phase difference between two points in one pulse of the received signal can be calculated without ambiguity (so as not to erroneously detect a value that is an integral multiple of π).

Embodiment 3 FIG.
A radar apparatus according to Embodiment 3 of the present invention will be described with reference to FIGS. FIG. 7 is a block diagram showing a configuration of a radar apparatus according to Embodiment 3 of the present invention.

  7, the radar apparatus according to Embodiment 3 of the present invention includes a pulse specification setting unit 1, a pulse waveform generation unit 2, a transmission unit 3, a circulator 4, an antenna unit 5, and a reception unit 6. The A / D converter 7, the pulse intermediate detector 12, the pulse signal analyzer 8, the phase detector 9, and the Doppler velocity calculator 10 are provided.

  Next, the operation of the radar apparatus according to the third embodiment will be described with reference to the drawings.

FIG. 8 is a timing chart showing how to detect the time of the intermediate point of the received pulse signal of the radar apparatus according to Embodiment 3 of the present invention. 8, to determine the time t _m of the midpoint of the time t ₁ and t ₂ crossing the threshold and the midpoint of the pulse.

FIG. 9 is a timing chart showing an intermediate point and two points in one pulse of the radar apparatus according to Embodiment 3 of the present invention. In FIG. 9, two time points t ₁ and t ₂ that are separated by an equal time from the intermediate point time t _m are detected. As will be _{t 2 -t m = t m -t} 1, the time _{t 1} and _{t 2} is detected.

  In the first embodiment, two points in one pulse intersect with the threshold value. The third embodiment is characterized in that the middle of one pulse is detected and two points are defined so as to be separated by an equal width from the middle point of the pulse. An example in this case will be described.

The pulse intermediate detection unit 12 has a function of detecting the time of the intermediate point of the pulse in one pulse with respect to the reception signal output from the A / D conversion unit 7. FIG. 8 shows how the time of the intermediate point of the pulse is detected. In FIG. 8, the voltage envelope of the received signal is compared with a preset threshold value to find a point that intersects the threshold value. The middle of the intersecting point is set as the middle point of the pulse. The pulse intermediate detector 12 outputs a time t _m at the intermediate point of the pulse. The received signal used for analysis is also output.

As shown in FIG. 9, the pulse signal analysis unit 8 determines the intermediate point of the pulse based on the time t _m of the intermediate point of the pulse from the pulse intermediate detection unit 12 and the pulse width information from the pulse specification setting unit 1. Two times t ₁ and t ₂ separated by an equal time so as not to exceed the pulse width time are detected from time t _m , and output as _two times t ₁ and t _{2 in one} pulse. .

  As described above, according to the third embodiment, the time difference between two points in one pulse can be always set to the same value. Therefore, when calculating the Doppler frequency over a plurality of pulses, Since two points in the pulse can always be defined at the same time interval, and the calculation of the time difference Δt in equation (4) can be omitted, the Doppler frequency can be calculated more efficiently.

Embodiment 4 FIG.
A radar apparatus according to Embodiment 4 of the present invention will be described with reference to FIGS. 10 and 11. FIG. 10 is a block diagram showing a configuration of a radar apparatus according to Embodiment 4 of the present invention.

  10, the radar apparatus according to Embodiment 4 of the present invention includes a pulse specification setting unit 1, a pulse waveform generation unit 2, a transmission unit 3, a circulator 4, an antenna unit 5, and a reception unit 6. , A / D conversion control unit 13, A / D conversion unit 7a, A / D conversion unit (second A / D conversion unit) 7b, peak value analysis unit 14, phase detection unit 9, and Doppler A speed calculation unit 10 is provided.

  Next, the operation of the radar apparatus according to the fourth embodiment will be described with reference to the drawings. FIG. 11 is a timing chart showing how received signals are sampled by a radar apparatus according to Embodiment 4 of the present invention.

  In the first embodiment, the A / D converter 7 performs analog / digital conversion of the received signal at high speeds at regular intervals. The fourth embodiment is characterized in that analog / digital conversion is performed at a low speed, and an example in this case will be described.

  The A / D conversion control unit 13 has a function of controlling the analog / digital conversion start timing and sampling interval of the A / D conversion units 7a and 7b based on the information of the pulse specifications from the pulse specification setting unit 1. .

  The peak value analysis unit 14 has a function of detecting the peak value of the digital signals output from the A / D conversion units 7a and 7b and detecting the time corresponding to the peak value.

  The A / D conversion control unit 13 determines the analog / digital conversion start timing for the A / D conversion units 7a and 7b based on the pulse width information of the transmission signal obtained from the pulse specification setting unit 1. The A / D conversion unit 7b performs analog / digital conversion at the same time as the pulse width for the sampling interval so that the A / D conversion unit 7a is delayed by a delay time shorter than the pulse width. To control. By this control, two points with a time interval shorter than the pulse width can be sampled with respect to the same received signal as shown in FIG.

  The peak value analysis unit 14 inputs the digitized reception signals from the A / D conversion units 7a and 7b. Since both digitized received signals are sampled at intervals of the pulse width, the pulse signal can be detected at any sampling point. Peak values with the same data sample number for data within the time range corresponding to the pulse repetition time of the transmission signal from the digitized reception signals output from the A / D conversion units 7a and 7b Are determined as two points in one pulse, and each time is output.

  As described above, according to the fourth embodiment, since the analog / digital conversion of the received signal is performed at intervals of the pulse width, the number of data points to be sampled is calculated when there is no received signal, that is, when there is no received pulse. Can be reduced. Further, there is an advantage that the pulse signal analysis unit 8 used in the first embodiment is not necessary.

Embodiment 5 FIG.
A radar apparatus according to Embodiment 5 of the present invention will be described with reference to FIGS. FIG. 12 is a block diagram showing a configuration of a radar apparatus according to Embodiment 5 of the present invention.

  12, the radar apparatus according to Embodiment 5 of the present invention includes a pulse specification setting unit 1, a pulse waveform generation unit 2, a transmission unit 3, a circulator 4, an antenna unit 5, and a reception unit 6. The A / D conversion unit 7, the guard interval detection unit 15, the pulse signal analysis unit 8, the phase detection unit 9, and the Doppler velocity calculation unit 10 are provided.

  Next, the operation of the radar apparatus according to the fifth embodiment will be described with reference to the drawings. FIG. 13 is a timing chart showing signal transmission characteristics of the radar apparatus according to Embodiment 5 of the present invention. FIG. 14 is a timing chart showing how two points are selected within one pulse of a radar apparatus according to Embodiment 5 of the present invention.

  In the first embodiment, when the pulse signal analysis unit 8 defines two points in the pulse, any point in the pulse is defined. The fifth embodiment is characterized in that the selection prohibited area is designated so as not to define a point near the rising edge in the pulse, and an example in this case will be described.

  The guard interval detector 15 has a function of detecting a rising portion of the pulse signal from the received signal, designating a minute time as a selection prohibited area from the rising time, and outputting a time zone of the selection prohibited area.

  As shown in FIG. 13, a vibration called ringing may occur at the rising edge of the pulse depending on the signal transmission characteristics of the radar apparatus. When this vibration is significant, if a threshold value is set and a point where the threshold value is crossed is specified, three or more points will be selected in one pulse, and confusion will occur in the subsequent calculation of Doppler frequency. Occurs. For this reason, the guard interval detection unit 15 detects the pulse rising from the digitized reception signal output from the A / D conversion unit 7 and determines the pulse width from the pulse width information obtained from the pulse specification setting unit 1. The time at which the vibration stops within the time of is detected. The point where the vibration stops is the point where the slope of the voltage envelope of the pulse starts to take a set value close to zero. The time between the time at the point and the rise time of the pulse is designated as a selection prohibited area.

  When two points are selected within one pulse, the pulse signal analysis unit 8, as shown in FIG. 14, if the point with the earlier time is within the selection prohibited area, the point is outside the selection prohibited area. Slide to detect the time at that point.

  As described above, according to the fifth embodiment, when vibration occurs at the rising edge of the received signal, it is possible to make it impossible to select the range in which vibration occurs. It is possible to prevent the points beyond the points from being defined.

It is a block diagram which shows the structure of the radar apparatus which concerns on Embodiment 1 of this invention. It is a timing chart which shows a mode that the time of two points | pieces of the received pulse signal of the radar apparatus which concerns on Embodiment 1 of this invention is detected. It is a timing chart which shows a mode that the time of two points | pieces of the received pulse signal of the radar apparatus which concerns on Embodiment 1 of this invention is detected. It is a block diagram which shows the structure of the radar apparatus which concerns on Embodiment 2 of this invention. It is a timing chart which shows one pulse signal of the received signal and transmission signal of the radar apparatus which concerns on Embodiment 2 of this invention. It is a timing chart which shows the phase relationship of the transmission signal of the radar apparatus which concerns on Embodiment 2 of this invention, and a received signal. It is a block diagram which shows the structure of the radar apparatus which concerns on Embodiment 3 of this invention. It is a timing chart which shows a mode that the time of the intermediate point of the received pulse signal of the radar apparatus which concerns on Embodiment 3 of this invention is detected. It is a timing chart which shows the middle point and two points in one pulse of the radar apparatus concerning Embodiment 3 of this invention. It is a block diagram which shows the structure of the radar apparatus concerning Embodiment 4 of this invention. It is a timing chart which shows the mode of the sampling of the received signal of the radar apparatus which concerns on Embodiment 4 of this invention. It is a block diagram which shows the structure of the radar apparatus which concerns on Embodiment 5 of this invention. It is a timing chart which shows the signal transmission characteristic of the radar apparatus concerning Embodiment 5 of this invention. It is a timing chart which shows a mode that two points | pieces are selected within one pulse of the radar apparatus which concerns on Embodiment 5 of this invention.

Explanation of symbols

  1 pulse specification setting unit, 2 pulse waveform generation unit, 3 transmission unit, 4 circulator, 5 antenna unit, 6 reception unit, 6A reception unit, 7 A / D conversion unit, 7A A / D conversion unit, 7a A / D Conversion unit, 7b A / D conversion unit, 8 pulse signal analysis unit, 8A pulse signal analysis unit, 9 phase detection unit, 9A phase detection unit, 10 Doppler velocity calculation unit, 11 phase correction unit, 12 pulse intermediate detection unit, 13 A / D conversion control unit, 14 peak value analysis unit, 15 guard interval detection unit.

Claims (5)

A pulse specification setting unit for setting the specifications of the transmission pulse signal;
A pulse waveform generation unit that generates a pulse signal based on the parameters set by the pulse parameter setting unit;
A transmission unit that generates a transmission signal by pulse-modulating a high-frequency signal, using the pulse signal generated by the pulse waveform generation unit as a modulation signal;
A circulator that performs path switching between a transmission signal and a reception signal;
An antenna unit that radiates a transmission signal toward a target and receives a signal reflected by the target;
A receiving unit that converts the frequency of the received signal received by the antenna unit into a low-frequency pulse signal;
An A / D converter that digitally converts the pulse signal frequency-converted by the receiver;
A pulse signal analysis unit that detects the time of two points within one pulse based on the parameters set by the pulse parameter setting unit with respect to the pulse signal digitally converted by the A / D conversion unit;
A phase detector for detecting phase values at two points of time detected by the pulse signal analyzer;
Wherein based on the wavelength of the detected phase value and the transmission signal obtained from the transmitting unit by the phase detector, the radar apparatus being characterized in that a Doppler velocity calculation unit for calculating a Doppler velocity of the target. A second receiver for converting the frequency of the transmission signal generated by the transmitter to a low-frequency pulse signal;
A second A / D converter that digitally converts the pulse signal frequency-converted by the second receiver;
A second time for detecting the time of two points in one pulse based on the specification set by the pulse specification setting unit for the pulse signal digitally converted by the second A / D conversion unit A pulse signal analysis unit;
A second phase detector for detecting phase values at two points of time detected by the second pulse signal analyzer;
A phase correction unit for correcting the phase value detected by the phase detection unit with reference to the phase value detected by the second phase detection unit;
The said Doppler velocity calculation part calculates the said target Doppler velocity based on the phase value correct | amended by the said phase correction part, and the wavelength of the transmission signal obtained from the said transmission part . Radar device. For the pulse signal digitally converted by the A / D converter, further comprising a pulse intermediate detector that detects the time of an intermediate point in one pulse,
The pulse signal analysis unit, based on the specifications set by the pulse specification setting unit, sets two points of time separated from the time of the intermediate point detected by the pulse intermediate detection unit by the same time before and after. The radar apparatus according to claim 1, wherein the radar apparatus detects the time at two points in the pulse. A second A / D converter that digitally converts the pulse signal frequency-converted by the receiver;
Start of analog / digital conversion for the A / D converter and the second A / D converter based on the pulse width of the transmission signal that is part of the specifications obtained from the pulse specification setting unit Regarding the timing, the second A / D converter is delayed by a delay time shorter than the pulse width with respect to the A / D converter, and the sampling interval is analog at the same time as the pulse width. A / D conversion control unit that controls to perform digital conversion;
Instead of the pulse signal analysis unit, the pulse signal digitally converted by the A / D conversion unit and the second A / D conversion unit has a cycle of the pulse width of the transmission signal. The radar apparatus according to claim 1, further comprising: a peak value analysis unit that samples two points at a short time interval and detects two points in one pulse. A guard interval detection unit that detects a selection prohibited area from the rise time of the pulse signal digitally converted by the A / D conversion unit to the point of time when the vibration is stopped;
When the pulse signal analysis unit detects two points of time in one pulse, if the earlier point is within the selection prohibited region detected by the guard interval detection unit, The radar apparatus according to claim 1, wherein the point is slid to a place where the point is and the time of the slid point is detected.

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