JP3508631B2 - Doppler observation equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a Doppler observation device for measuring wind speed and direction above an observation position and providing altitude distribution information above the observation position.

[0002]

2. Description of the Related Art Conventionally, a meteorological observation in the sky has been conducted by using a sonde, etc., but in the sonde observation, only the data at the time when the sonde is raised can be obtained, and the observation data usually has a low time resolution. (For example, every few hours). On the other hand, in recent years, a Doppler radar that can measure a wind field called a wind profiler densely in space and time has been widely used. According to such a Doppler radar, a higher time resolution (for example, 1 minute ~ Number 10
It is possible to measure the wind direction and speed above the observation position in minutes.

For example, Japanese Laid-Open Patent Publication No. 10-197549 discloses a phased array antenna type Doppler which measures the horizontal component of the wind speed above the observation position, taking into consideration possible measurement errors and topographical conditions. An anemometer (a so-called Doppler radar) is described. Then, according to the measurement data of the wind speed and the wind direction measured with such a high time resolution, it is possible to accurately calculate the altitude distribution of the atmosphere above the observation position, and based on this altitude distribution data, for example, It becomes possible to more accurately detect the occurrence status of air pollution, the detection of turbulence that obstructs aviation of aircraft, and the prediction of local rainfall status.

[0004] For example, the weather information provided by the Meteorological Agency has been conventionally used in the prediction of rainfall conditions, but such forecast information from the Meteorological Agency is based on the observation data observed over a wide area. (For example, the data of AMeDAS measures the amount of rainfall in each section divided into 5km squares.) Although it was not possible to accurately predict the local rainfall situation, With such Doppler radar, it is possible to observe the altitude distribution above the observation position with higher time resolution, so the rainfall scale around the observation position, the rainfall position, etc. can be determined based on such altitude distribution information. By predicting, the location and scale of heavy rainfall can be predicted more accurately,
It can be expected to be utilized for disaster prevention (in mountainous areas with a large number of water systems, more accurate forecasting of rainfall conditions is necessary to prevent the occurrence of disasters due to such heavy rainfall).

[0005]

However, the conventional Doppler radar measures the horizontal wind assuming that the wind is uniform (provided that the wind velocity distribution in the horizontal plane is substantially uniform). Is configured as described in Japanese Patent Laid-Open No. 10-1
If the zenith angle of the oblique antenna beam at the time of radio wave reception is constant regardless of the observation altitude, as in the Doppler anemometer described in Japanese Patent No. 97549, the observation altitude is The higher the height, the wider the observation area becomes, which is the area where the wind is assumed to be uniform, and the higher the observation altitude area, the wider the observation area of the wind becomes. However, there was a problem of deterioration.

Further, in order to minimize the deterioration of the observation accuracy due to such non-uniform wind distribution, when the zenith angle of the oblique antenna beam at a high observation altitude is set small, the atmosphere in the low observation altitude region is Since the Doppler velocity (projection component) becomes small, it is difficult to distinguish it from the topographic echo, and there is a problem that the observation accuracy at low observation altitude deteriorates.

The present invention has been made in order to solve the above problems, and enables accurate measurement of wind speed and wind direction (hereinafter, simply referred to as horizontal wind) regardless of the observation altitude. It is an object of the present invention to provide a new Doppler observation device capable of observing more accurate altitude distribution information and the like from the results. It is another object of the present invention to provide a novel Doppler observation device which can shorten the measurement time for the wind speed and the wind direction and has improved observation efficiency.

A Doppler observation apparatus according to claim 1 of the present invention includes an antenna unit for scanning an antenna beam, and an antenna unit for scanning the antenna beam.
The transmitter and receiver that sends and receives signals to and from the antenna
The antenna part is fan-beam type when transmitting, and the pencil type when receiving.
It controls to a low beam type, and the antenna beam is low altitude when receiving.
Beam control unit that changes from high to high altitude, and the above antenna
A position that is separated from the observation position of the center by a predetermined distance in the horizontal direction.
Multiple calculation points of the Doppler shift amount in the zenith direction at
The zenith angle of the antenna beam corresponding to each calculation point is set up.
Control means for instructing the beam control section to control the reception timing of the transmission / reception section, and reception means from the antenna section.
Signal processing to detect the amount of Doppler shift of the atmosphere from the received radio waves
And a section .

A Doppler observation apparatus according to claim 2 of the present invention
Position is to change the antenna beam discretely.
It is the one according to claim 1 characterized.

A Doppler observation apparatus according to claim 3 of the present invention
The terrain is based on the detection results of the Doppler shift amount and the terrain echo
The effect of
The feature is that the zenith angle pattern of the dome is changed.
It is the one according to claim 1.

[0011]

[0012]

[0013]

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1 An embodiment of the present invention will be described below with reference to FIGS. 1 to 4. FIG. 1 is a block diagram showing a Doppler observation apparatus according to an embodiment of the present invention, and FIG.
FIG. 4 is a beam characteristic diagram of an antenna beam emitted or scanned by the Doppler observation device shown in FIG. Note that the beam characteristics of the antenna beam can be controlled by exciting the whole or part of the antenna aperture surface, and the Doppler observation apparatus according to the present embodiment can improve the observation efficiency from the viewpoint of radio wave transmission. Antenna beams having the beam characteristics shown in FIG. 2A and the beam characteristics shown in FIG.

In FIG. 1, reference numeral 1 denotes an element array 1a in which a plurality of antenna elements are arranged, and a transfer for supplying a predetermined phase signal to the element array 1a to form an antenna beam having a predetermined beam characteristic on an antenna aperture plane described later. Phased array type antenna section composed of phase shifter 1b, 2
Is a transmission unit that generates a transmission signal of a predetermined frequency to be transmitted from the antenna unit 1 to the sky above the observation position, and 3 is a reflection from a target object or the like received by the antenna unit 1 and input via the transmission / reception switching unit 4 such as a circulator. A receiving unit (5 is a transmitting / receiving unit including 2 to 4) that receives and processes radio waves, and 6 includes signal processing such as FFT conversion processing on the reception signal received by the receiving unit 3 and includes the reflected radio waves. A signal processing unit for detecting the Doppler shift amount of the selected frequency; 7 a beam control unit for instructing the phase shifter 1b to control the beam characteristics and beam direction of the antenna beam formed in the antenna unit 1; Has a CPU, a memory, etc., and calculates the horizontal wind above the observation position from the Doppler shift amount detected by the signal processing unit 6 in accordance with a built-in program or a command from an external device. To perform calculation processing of height distribution,
Further, it is a control means for instructing the beam control unit 6 to switch the antenna beam in accordance with the transmission / reception timing of radio waves. Various processing data calculated by the control means 8 (horizontal wind data over the observation position or altitude distribution data, etc.) is output to another device such as a display device and used for weather forecast ( (Not shown).

Further, in FIG. 2, 9 is an element array 1a.
Antenna aperture planes 10a and 10b are antenna aperture planes 9
Is an antenna beam (hereinafter, referred to as an oblique antenna beam) formed obliquely above the sky, and 10a is a directional characteristic of the oblique antenna beam during radio wave transmission.
b shows the directional characteristics of the diagonal antenna beams when receiving radio waves. As shown in FIG. 2, in the Doppler observation apparatus according to the present embodiment, a so-called fan-beam type antenna beam having broad directional characteristics in the elevation angle direction is formed during radio wave transmission, and is compared with the azimuth direction and elevation angle direction during radio wave reception. A so-called pencil beam type antenna beam having a sharp sharp directivity is formed. The oblique antenna beams 10a and 10b are angled from the zenith direction (hereinafter referred to as the zenith angle) with reference to the direction orthogonal to the antenna aperture plane 8, that is, the zenith direction.
The antenna elevation angle is controlled by.

In general, horizontal wind measurement by a Doppler radar detects oblique wind speeds of two oblique antenna beams having different azimuth angles with the zenith direction and different directions of transmitted and received radio waves projected on a horizontal plane. This is performed by eliminating the vertical component from these oblique wind speeds and detecting the horizontal component (for example, the calculation method described in Japanese Patent Laid-Open No. 10-197549), and the Doppler observation device according to the present embodiment is also used. By the same calculation process, the moving speed of the atmosphere at each observation altitude is measured. For example, when observing a horizontal wind in the east-west direction, calculate the horizontal wind in the east-west direction above the observation position by removing the vertical component from the measurement value in the east or west diagonal direction and the measurement value in the zenith direction, or The vertical component is removed from the measurement values diagonally above the east direction and the measurement values diagonally above the west direction to calculate the horizontal wind in the east-west direction above the observation position.

Although FIG. 2 shows the case of measuring horizontal winds in the east-west direction, the same applies to the case of measuring horizontal winds in other azimuth directions as well. Horizontal winds above the observation position are calculated by dimensional composite vector processing (E is east direction,
W is west, N is north, and S is south. ).

Next, the operation of the Doppler observation apparatus according to the present embodiment will be described by taking the horizontal wind measurement in the east-west direction as an example (the description of the calculation of the horizontal winds in other azimuth directions will be omitted). FIG. 3 is a transmission / reception timing explanatory diagram for explaining the transmission / reception timing of the Doppler observation apparatus according to the present embodiment and the change of the beam zenith angle during reception of radio waves. In the Doppler observation apparatus according to this embodiment, when the transmission operation is started, first, the control unit 8 instructs the transmission unit 2 of the transmission / reception unit 5 to transmit, and the beam control unit 7 to instruct the antenna unit 1. The oblique antenna beam 10a having the characteristics shown in FIG. 2A is formed. Then, the transmission signal of the predetermined frequency output from the transmission unit 2 is
This oblique antenna beam 10a is transmitted via the transmission / reception switching unit 4 and the antenna unit 1 to the sky above the observation position as a transmission radio wave. Here, the diagonal antenna beam 10a is shown in FIG.
It is an antenna beam having a wide beam characteristic in the elevation angle direction including the vicinity of the zenith direction as shown in (a).
The transmission signal output from can be transmitted over the entire observation area in a relatively short transmission time (see FIG. 11, upper stage FIG. 3).

Next, when the reception operation is started, the control means 8 instructs the transmission / reception section 5 to switch between transmission and reception, and
The beam control unit 7 is controlled to switch the diagonal antenna beam 10a formed on the antenna aperture 9 to the pencil beam type diagonal antenna beam 10b as shown in FIG. 2B. Then, the beam control unit 7 controls the oblique antenna beam 10b as described later to receive the reflected radio wave reflected from a non-uniform place in the atmosphere. Since the oblique antenna beam 10b at the time of receiving a radio wave has a narrow beam width in the elevation direction, it takes some time to scan the inside of the observation region and cover the entire observation region (see middle stage FIG. 12 of FIG. 3). In the present embodiment, the scanning procedure of the oblique antenna beam 10b is controlled so as to change from the direction in which the zenith angle is large to the direction in which the zenith angle is small (FIG. 3).
See FIG. 13 at the bottom. ), The reflected radio waves from each observation altitude region can be efficiently received.

That is, in the pulse radar, the time difference between transmission and reception corresponds to the distance from the observation position, and the distribution in the distance direction between the observation position and the target can be measured from the reception data of the received reflected waves in time series. However, in the Doppler observation apparatus according to the present embodiment, the beam control unit 7 uses such a target (here, a nonuniform portion of the atmosphere such as a fluctuation due to the atmospheric composition or a fluctuation due to the atmospheric density, hereinafter referred to as a scatterer). To a high observation altitude region where the distance to the scatterer is long (that is, in the elevation direction where the zenith angle is small). Since the oblique antenna beam 10b is scanned so as to change the zenith angle and the reflected radio waves from the scatterer are received, there is a time difference according to the distance to the scatterer. Is reflected radio wave can be received from each scatterer with the reflected waves from the atmosphere at the observation position over can be received efficiently.

The scanning speed of the oblique antenna beam 10b is set according to the weather conditions around the observation position, the required observation accuracy, etc., but with the Doppler observation apparatus according to this embodiment, The scanning speed of the oblique antenna beam 10b and the reception timing of the receiving unit 3 are set so that the observation region in, that is, the calculated position of the horizontal wind becomes equal at each observation altitude.

Then, the projection components (obtained by eliminating the vertical component from the oblique wind speed) are calculated for the time-series reception data received by the oblique antenna beam 10b and processed by the receiving unit 3. By doing so, the horizontal wind at each observation altitude can be measured. As described above, the principle of horizontal wind measurement is based on the fact that the density of the refractive index in the atmosphere is reflected as a scatterer and the change in frequency due to the Doppler effect of this reflected wave is detected. In the Doppler observation device in the form of, the Doppler shift amount from such reflected radio waves is detected by the Doppler processing unit 6, and the horizontal wind is calculated based on these time-series Doppler shift amounts to obtain each observation altitude. The horizontal wind for each can be calculated.

FIG. 4 is a measurement situation explanatory view schematically showing the measurement situation of the horizontal wind at the time of radio wave reception of the Doppler observation apparatus according to this embodiment. As shown in FIG. The Doppler device controls the scanning of the oblique antenna beam 10b and the reception timing of the receiving unit 3 so that the horizontal wind observation regions (horizontal wind calculation points S1 to Sn) at the respective observation altitudes become equal.
In the case where there is spatially non-uniform wind distribution over the observation position, the area assuming the uniformity of wind does not inadvertently expand even at high observation altitude regions, and horizontal winds at each observation altitude The measurement accuracy can be improved.
In FIG. 4, K1 to Kn (n is an integer) are observation altitudes at which the horizontal wind is measured, and S1 to Sn are horizontal wind calculation points at the respective observation altitudes.

Then, the horizontal wind measurement as described above is performed in a plurality of azimuth directions (including the north and south directions) with the observation position as the center.
It is possible to measure horizontal winds at each observation altitude for a large number of azimuth directions, and to measure horizontal winds at each observation altitude for each azimuth direction.
The three-dimensional distribution of horizontal winds above the observation position can be calculated by performing the dimensional vector synthesis process. The altitude distribution of the atmosphere above the observation position is observed based on this three-dimensional distribution of horizontal wind.

As described above, according to the Doppler observation apparatus according to this embodiment, when transmitting a radio wave, a transmission signal is transmitted by an antenna beam having a wide beam characteristic in the elevation angle direction as shown in FIG. Fig. 2 when receiving radio waves
Since the antenna beam having a beam characteristic with a narrow beam width in the elevation direction as shown in (b) is changed from a direction in which the zenith angle is large to a direction in which the zenith angle is small, the reflected radio wave is received. High-speed transmission and reception of radio waves to the sky, measurement efficiency of horizontal winds above the observation position,
As a result, the observation efficiency of the altitude distribution can be greatly improved. Further, since the horizontal wind observation areas are made equal regardless of the observation altitude, it is possible to improve the wind measurement accuracy at each observation altitude and observe a more accurate atmospheric altitude distribution.

Further, if the altitude distribution of the atmosphere above the observation position can be accurately observed, it is possible to more accurately predict the change in the local meteorological phenomenon around the observation position as described above, for example, the rainfall situation. Therefore, it is possible to use it for disaster prevention, such as avoiding a disaster, to monitor the occurrence of air pollution with higher accuracy, and to detect turbulence that interferes with aircraft aviation.

Embodiment 2. Next, another embodiment of the present invention will be described. In the Doppler observation apparatus according to the above embodiment, the oblique antenna beam 10 at the time of radio wave reception is received.
The zenith angle of b changed continuously with the passage of time, but the range of changing this zenith angle is extremely wide ranging from low elevation direction to high elevation direction (30 to 60 degrees?). In order to receive the reflected radio waves from the atmosphere over the entire observation area, the diagonal antenna beam 10
The scanning speed of b is limited. That is, if the scanning speed of the antenna beam is set too high, there is a problem that the time resolution is lowered and the wind measurement accuracy of the measured horizontal wind is also deteriorated. To obtain the desired time resolution, the scanning speed of the antenna beam is reduced. Cannot be set too fast.

In the Doppler observation apparatus according to this embodiment, in order to solve such a problem, the zenith angle of the oblique antenna beam 10b at the time of radio wave reception is discretely changed corresponding to the observation altitude. . Such a change in the zenith angle of the oblique antenna beam 10b is realized, for example, by the control of a program or the like preset in the control means 8, and a device outline of the Doppler observation device according to the present embodiment is shown in FIG. The configuration is almost the same as that shown (a detailed description of the device is omitted.). FIG. 5 is a transmission / reception timing for explaining a state in which the beam zenith angle of the oblique antenna beam 10b is discretely changed. It is an explanatory view, and in the Doppler observation apparatus according to the present embodiment, the beam zenith angle of the oblique antenna beam is changed into three levels for low altitude, middle altitude, and high altitude (see the lower diagram in FIG. 5). reference.).

According to the Doppler observation apparatus according to the present embodiment, as shown in FIG. 5, it is possible to set the reception time of the reflected radio wave at a predetermined observation altitude to be long, and the Doppler observation apparatus according to the above-mentioned embodiment is provided. Moreover, the time resolution of the received radio wave can be significantly improved as compared with the case where the diagonal antenna beam is continuously changed. Although the zenith angle of the oblique antenna beam is changed in three steps in this embodiment, it is desirable to measure horizontal winds at many observation altitudes in order to observe the altitude distribution of the atmosphere more accurately. The oblique antenna beam may be changed in multiple stages of three stages or more according to the required observation accuracy.

As described above, according to the Doppler observation apparatus according to this embodiment, the zenith angle of the oblique antenna beam at the time of radio wave reception is discretely changed.
Furthermore, the time resolution of the received reflected radio waves can be improved, the accuracy of horizontal wind measurement at each observation altitude is improved, and a more accurate altitude distribution of the atmosphere can be observed.
Moreover, since the time required for switching the beam zenith angle can be shortened, the horizontal wind measurement time can be shortened, and the observation efficiency can be improved while preventing the deterioration of the observation accuracy.

Embodiment 3. Next, another embodiment of the present invention will be further described with reference to FIGS. 6 and 7. In each of the above-described embodiments, the oblique antenna beam 10 at the time of radio wave reception is set so that the region where wind uniformity is assumed, that is, the observation region above the observation position is substantially constant regardless of the observation altitude.
Although the zenith angle of b was changed, in the Doppler observation device as described above, not only reflected waves from the atmosphere but also reflected waves from the ground surface and buildings around the observation position (hereinafter referred to as topographic echo). However, it may be difficult to distinguish between so-called atmospheric echoes and topographic echoes at observation positions that are easily affected by topographic echoes. affect.

The Doppler observation apparatus according to this embodiment is
In order to eliminate such problems, so-called terrain echo was evaluated for the measured horizontal wind, and the observation altitude determined from the evaluation results of this terrain echo was that the wind measurement accuracy was deteriorated due to the terrain echo, The zenith angle pattern of the oblique antenna beam 10b is changed, and the horizontal wind is measured again at the changed zenith angle.

FIG. 6 is an operation flowchart showing an operation flow of the Doppler observation apparatus according to this embodiment. This operation flow is realized by, for example, a program preset in the control means 8. The device outline of the Doppler observation device according to the present embodiment is configured almost the same as that shown in FIG. 1, and the horizontal wind calculation process is similar to that of the Doppler observation device according to the above embodiments. Done by. In the Doppler observation apparatus according to this embodiment, first, radio waves are transmitted and received using the oblique antenna beams 10a and 10b as shown in FIGS. 2A and 2B, and the Doppler of the atmosphere above the observation position is transmitted. The shift amount is detected (S01). Then, the horizontal wind at each observation altitude is calculated from these Doppler shift amounts (S02), and the effect of topographic echo is evaluated for each calculated horizontal wind (S03).

As described above, since the Doppler observation device such as a wind profiler receives or analyzes weak radio waves reflected in the atmosphere to measure the moving speed of the atmosphere, the Doppler observation device is used to measure the moving speed of the atmosphere. When strong reflected radio waves are received from buildings, etc., it is easily affected by such topographic echo. That is, such a terrain echo generally has a detected Doppler shift amount of zero, and when the moving speed of the atmosphere above the observation position is very small, the Doppler shift amount of the atmosphere detected by the signal processing unit 6 is also small. When the so-called atmospheric echo and terrain echo are detected in an overlapping manner, it is difficult to identify them even if the spectra of these received data are compared (for example, the slope of a mountain Its surface is fluctuating, and the topographic echo reflected from such a slope does not have zero Doppler shift.

Here, a concrete evaluation as to whether or not the influence of the terrain echo is made may be made by whether or not the wind measurement accuracy is deteriorated. For example, the SN ratio, the speed range, the clutter level, etc. may be evaluated. It can be done based on. The evaluation of the terrain echo may be performed for the horizontal wind at each observation altitude obtained by the three-dimensional vector synthesis, or may be performed for each horizontal wind calculated in each azimuth direction. If the deterioration of the wind measurement accuracy is not detected from the evaluation result of the terrain echo as described above, the control means 8 determines that the horizontal wind measurement is normally performed, and the measurement is performed without changing the zenith angle pattern. When the altitude distribution above the observation position is calculated based on the horizontal wind at each observation altitude, and the deterioration of the wind measurement accuracy is detected, the level of the horizontal wind The change of the zenith angle pattern of the oblique antenna beam 10b is instructed to perform the measurement (S04).

Specifically, the control means 8 instructs the beam control section 7 to change the zenith angle pattern of the oblique antenna beam 10b, and the beam control section 7 controls the beam to be formed on the antenna aperture 9. Diagonal antenna beam 1
The zenith angle pattern of 0b is changed. FIG. 7 is a zenith angle pattern explanatory view showing a state in which the zenith angle of the oblique antenna beam 10b is changed based on the evaluation of the terrain echo. In the Doppler observation device according to the present embodiment, as shown in FIG. The oblique antenna beam 10b so that the observation area becomes wider at the observation altitude where the influence of
Is changed, and the horizontal wind at the observation altitude is measured again at the zenith angle of the oblique antenna beam 10b after the change (in FIG. 7, S1 is the horizontal wind calculation point before the change, S1 ′). Is the calculated horizontal wind calculation point.)

As described above, the horizontal wind is calculated based on the projection component of the antenna beam 10b in the line-of-sight direction. If the zenith angle of the antenna beam 10b is increased, the projection component is increased accordingly. Even if the speed of movement of the atmosphere is very small and it is difficult to distinguish from the topographic echo, widening the zenith angle makes it easier to distinguish between the atmospheric echo and the topographic echo, and the horizontal wind measurement in the observation altitude region is performed. The accuracy can be improved.
The effect of topographic echo tends to increase as the observation altitude region decreases, and is hardly affected at high observation altitudes.

As described above, according to the Doppler observation apparatus according to the present embodiment, the terrain echo is evaluated for the measured horizontal wind, and when the deterioration of the wind measurement accuracy due to the terrain echo is detected, the radio wave is detected. Since the zenith angle pattern of the oblique antenna beam 10b at the time of reception is changed and the horizontal wind is measured again, it is possible to easily distinguish what is called an atmospheric echo and a terrain echo, and further, a more accurate atmospheric The altitude distribution can be observed. In addition, the effect of topographic echo tends to increase as the observation altitude becomes lower, and does not significantly affect the measurement of horizontal wind at high observation altitude. Is less likely to occur.

From the evaluation result of the topographic echo as described above, it is possible to assume a case where the influence of the topographic echo cannot be prevented even by the change of the beam zenith angle pattern. The Doppler observation device may be placed on a moving body such as an automobile to serve as a vehicle-mounted Doppler observation device so that the observation position can be changed. The advantage of such an on-board Doppler observation device is that accurate observation of horizontal wind can be performed, for example, when the topographic echo object (mountain, building, etc.) that causes the topographic echo cannot be removed. Therefore, it is possible to measure horizontal winds over a plurality of observation positions or observe altitude distribution with one Doppler observation device. The Doppler observation means may be fixed to the moving body by an ordinary fixing means or the like.

Fourth Embodiment Next, another embodiment of the present invention will be described. In the Doppler observation device according to each of the above-mentioned embodiments, in order to improve the wind measurement accuracy and improve the observation efficiency of the altitude distribution, a so-called fan beam type antenna beam and a pencil beam type antenna beam are used for horizontal wind measurement. , And the horizontal wind may be measured by using a pencil beam type antenna beam for both transmission and reception. In this case, unlike the Doppler observation apparatus according to the above-described embodiment, it is necessary to repeatedly transmit and receive radio waves in order to cover the entire observation area, and accordingly, it takes time to measure the horizontal wind. As described above, by setting the zenith angle of the antenna beam to an angle corresponding to each observation altitude and measuring, the horizontal wind observation area becomes equal regardless of the observation altitude, and the horizontal wind measurement accuracy at each observation altitude becomes It is possible to improve and observe the altitude distribution of the atmosphere more accurately.

As described above, according to the present invention, the accuracy of horizontal wind measurement at each observation altitude can be improved.

[0043]

[0044]

[0045]

[0046]

[0047]

[Brief description of drawings]

FIG. 1 is a block diagram showing a Doppler observation device according to an embodiment of the present invention.

FIG. 2 is a beam explanatory diagram of an antenna beam emitted or scanned by the Doppler observation device shown in FIG.

FIG. 3 is a transmission / reception timing explanatory diagram for explaining transmission / reception timing of the Doppler observation device shown in FIG. 1 and a change in zenith angle of an oblique antenna beam when a radio wave is received.

FIG. 4 is an explanatory view of observation showing a change situation of a zenith angle or an elevation angle of an antenna beam at the time of reception by the Doppler observation device shown in FIG. 1.

FIG. 5 is a transmission / reception timing explanatory diagram of an oblique antenna beam for explaining a Doppler observation device according to another embodiment of the present invention.

FIG. 6 is an operation flowchart showing an operation flow of the Doppler observation apparatus according to another embodiment of the present invention.

FIG. 7 is a zenith angle pattern explanatory diagram showing a state in which the zenith angle of the oblique antenna beam 10b is changed based on the evaluation of the terrain echo.

[Explanation of symbols]

1 antenna section, 2 transmitter section, 3 receiver section, 4 transmission / reception switching section, 6 Doppler processing section, 7 beam control section, 8
Control means, 9 Antenna aperture, 10a, 10b Antenna beam

Continuation of the front page (72) Inventor Junhisa Tsuchimoto 730-11 Kamimachiya, Kamakura City, Kanagawa Mitsubishi Electric Tokuhoki System Co., Ltd. (56) References JP-A-10-197549 (JP, A) JP-A-9 -281131 (JP, A) JP-A-9-90034 (JP, A) JP-A-8-5737 (JP, A) JP-A-10-288665 (JP, A) JP-A-11-281740 (JP, A) ) JP 2000-338238 (JP, A) JP 62-274228 (JP, A) JP 11-271443 (JP, A) JP 6-174823 (JP, A) JP 54-43493 (JP, A) JP 62-44227 (JP, B2) JP 7-13657 (JP, B2) JP 6-4533 (JP, B2) JP 60-34067 (JP, B2) JP Table 7-502341 (JP, A) Patent 3393183 (JP, B2) Tomoya Matsuda, Hiroyuki Hashiguchi, Shinichiro Watanabe, Toshio Wakayama, Toshitaka Tsuda, Toru Sato, Yamanaka University, Mamoru Yamamoto, Takuji Nakamura, Shoichiro Fukao, "Milli" Wave doppler radar Development and its initial observation results ", Atmospheric Symposium, Japan, Institute of Space Science, March 5, 1998, 12th, 1997, p. 42-45 Tomoya Matsuda, Hiroyuki Hashiguchi, Shinichiro Watanabe, Toshio Wakayama, Shoichiro Fukao, "Development of Observation Method of Atmospheric Motions Using Millimeter-Wave Doppler Radar", Atmospheric Symposium, Japan, Space Science Research Institute, 1998 3 March 4th, 13th 1998, p. 60-63 (58) Fields surveyed (Int.Cl. ⁷ , DB name) G01W 1/00-1/18 G01S 13/00-13/95 G01P 5/00-5/26 G01P 13/00-13 / 04 JISST file (JOIS)

Claims (3)

(57) [Claims] 1. An antenna unit for scanning an antenna beam
And a transmission / reception unit that transmits / receives transmission / reception signals to / from this antenna unit
And, the antenna part is received in a fan-beam type when transmitting.
Sometimes it is controlled by the pencil beam type, and the antenna beam is received when receiving.
A beam control unit for high altitude change the beam from a low altitude, above
Note: A certain distance in the horizontal direction from the observation position of the antenna section
Multiple Doppler shifts in the zenith direction at separate positions
Of the antenna beam corresponding to each calculation point
The zenith angle instructed to the beam control unit, receiving of the transceiver unit
Control means for controlling the signal timing and the antenna section.
The amount of atmospheric Doppler shift is detected from the received radio waves.
Doppler observation apparatus characterized by comprising a signal processing unit that. 2. The Doppler observation apparatus according to claim 1, wherein the antenna beam is discretely changed. 3. The zenith angle pattern of the antenna beam is changed in accordance with the evaluation result of the topographic echo from the detection result of the Doppler shift amount, and the zenith angle pattern of the antenna beam is changed according to the evaluation result. Doppler observation device.