JP5443867B2 - Weather radar apparatus and radar signal processing method - Google Patents

Description

  The present invention relates to a meteorological radar apparatus and a radar signal processing method for observing meteorological phenomena such as rain and clouds.

  A conventional parabona antenna type weather radar forms a thin beam called a pencil beam, rotates 360 ° horizontally to acquire observation data for one plane, and then increases the antenna elevation to acquire the next plane. Continue to collect 3D precipitation data. The signal processing apparatus outputs polar coordinate data and performs orthogonal coordinate transformation when combining radar data at each site (see, for example, Non-Patent Document 1).

Supervised by Takashi Yoshida, “Revised Radar Technology”, The Institute of Electronics, Information and Communication Engineers, October 1, 1996, first edition, “Chapter 9 Weather Radar”, P238-253

  However, when a weather radar is configured using a phased array antenna, multiple beams can be processed simultaneously. However, since the data rate of the signal processing of the radar reception signal becomes high, there is a problem that the processing load of the signal processing device increases and the processing cannot catch up.

  The present invention has been made paying attention to the above circumstances, and an object thereof is to provide a weather radar apparatus and a radar signal processing method capable of reducing the processing load of a radar reception signal.

In order to achieve the above object, a weather radar apparatus according to the present invention forms a plurality of radar beams in an elevation direction by phase control from a plurality of antenna elements and transmits radio waves by sequentially changing the azimuth direction. An antenna unit that receives a reflected wave of the received wave, a received beam forming unit that forms a plurality of received beams based on a received signal of the reflected wave, and the received beam is mapped from a three-dimensional polar coordinate mesh to a three-dimensional orthogonal coordinate mesh, A signal processing unit that selects one reception beam when the orthogonal coordinate mesh includes a plurality of reception beams , synthesizes the beam based on the selected reception beam, and outputs reception data of an orthogonal coordinate system; It comprises.

Also, the radar signal processing method according to the present invention forms a plurality of radar beams in the elevation angle direction by phase control from a plurality of antenna elements, transmits radio waves by sequentially changing the azimuth direction, and reflects reflected waves from a weather target. A radar signal processing method used in a radar apparatus including an antenna unit for receiving, wherein a plurality of received beams are formed by the received signal of the reflected wave, and the received beams are changed from a three-dimensional polar coordinate mesh to a three-dimensional orthogonal coordinate mesh. When a plurality of received beams are included in the orthogonal coordinate mesh, one received beam is selected , beam synthesis is performed based on the selected received beam, and received data in an orthogonal coordinate system is output. Is.

  Therefore, according to the present invention, it is possible to provide a meteorological radar apparatus and a radar signal processing method capable of reducing the processing load of a radar reception signal.

The figure which shows the structural example of the weather radar apparatus which concerns on one Embodiment of this invention. The flowchart which shows operation | movement of the signal processing apparatus shown in FIG. The figure which shows the example of a mapping process to a rectangular coordinate mesh.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a configuration example of a weather radar apparatus according to an embodiment of the present invention.
In FIG. 1, the weather radar apparatus includes an antenna apparatus 1, a signal processing apparatus 2, a data processing apparatus 3, and a monitoring control apparatus 4.

  The antenna apparatus 1 includes, for example, a one-dimensional phased array antenna in which a plurality of antenna elements are arranged in the vertical direction. The aerial device 1 transmits radio waves from the plurality of antenna elements according to a control signal from the signal processing device 2, scans by forming a plurality of beams in an elevation angle direction by phase control, and from a weather target such as precipitation. Receive reflected waves.

  Further, since the weather radar device needs to observe a weather target in an arbitrary space, the antenna device 1 sequentially changes the azimuth direction of the antenna by the rotation of the drive motor or the like according to the control signal from the monitoring control device 4.

  On the other hand, when a reflected wave from a weather target in space is received, the antenna apparatus 1 A / D converts the received analog signal, performs I / Q detection, and the detected I / Q signal is signal processing apparatus 2. To give.

In the signal processing device 2, a DBF (Digital Beam Forming) processing unit 21 forms a plurality of reception beams by I / Q signals given from the antenna device 1. Receive data such as received power and Doppler speed is calculated. The signal processing device 2 stores in advance a coordinate conversion map 22 that can convert a three-dimensional polar coordinate mesh and a three-dimensional orthogonal coordinate mesh. The signal processing device 2 uses the coordinate transformation map 22 to map the plurality of reception beams formed as described above to a three-dimensional orthogonal coordinate mesh. When the mesh includes a plurality of reception beams, one signal is used. After selection, beam synthesis is performed to calculate received power, Doppler speed, and the like. That is, the reception data of the orthogonal coordinate system is output from the signal processing device 2.
Further, the signal processing device 2 transmits a phase control signal for determining the transmission angle of the radar radio wave to the antenna device 1 in accordance with the control signal from the monitoring control device 4.

The data processing device 3 calculates the rainfall intensity from the received power based on the reception data output from the signal processing device 2, and calculates the corrected Doppler velocity from the Doppler velocity.
The monitoring control device 4 sends control signals to each device based on a predetermined observation procedure, and collectively manages monitoring information of each device.

Next, radar signal processing in the weather radar apparatus configured as described above will be described. FIG. 2 is a flowchart showing the operation of the signal processing apparatus 2.
An I / Q signal is input from the antenna device 1 to the signal processing device 2, and the DBF processing unit 21 performs reception beam forming using the I / Q signal (step S2a). The signal processing device 2 maps the reception beam formed in step S2a to the orthogonal coordinate system using the coordinate transformation map 22 (step S2b). If the received beams overlap in the orthogonal coordinate mesh, one received beam is selected (step S2c). FIG. 3 shows an example of mapping processing to the Cartesian coordinate mesh. Here, for example, the reception beam having the largest ratio to the orthogonal coordinate mesh is selected. In addition, a reception beam located at the center of the mesh may be selected. The signal processing device 2 performs beam synthesis based on the reception beam selected in step S2c (step S2d), and outputs reception data in an orthogonal coordinate system (step S2e).

In a general radar apparatus, since the signal processing apparatus 2 performs processing in the polar coordinate system, the subsequent data processing apparatus 3 converts the data into Cartesian coordinate system data for display and the like. On the other hand, in the above-described embodiment, the reception beam formed by the DBF process in the signal processing device 2 is mapped to the orthogonal coordinate system, and the reception beam data overlapping on the orthogonal coordinate mesh is thinned out in advance. The target data can be reduced.
Therefore, according to the above embodiment, it is possible to realize a radar apparatus that can reduce the processing load of the radar reception signal.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment.

  DESCRIPTION OF SYMBOLS 1 ... Antenna apparatus, 2 ... Signal processing apparatus, 21 ... DBF processing part, 22 ... Coordinate conversion map, 3 ... Data processing apparatus, 4 ... Monitoring control apparatus.

Claims (6)

An antenna unit that forms a plurality of radar beams in the elevation angle direction by phase control from a plurality of antenna elements, transmits radio waves by sequentially changing the azimuth direction, and receives reflected waves from a weather target;
A reception beam forming unit for forming a plurality of reception beams by the reception signal of the reflected wave;
The received beam is mapped from a three-dimensional polar coordinate mesh to a three-dimensional orthogonal coordinate mesh, and when the orthogonal coordinate mesh includes a plurality of received beams, one received beam is selected , and the selected received beam is selected. And a signal processing unit that outputs the received data of the orthogonal coordinate system by combining the beams based on the meteorological radar apparatus. The weather radar apparatus according to claim 1, wherein the signal processing unit selects a reception beam having the largest ratio to the orthogonal coordinate mesh. The weather radar apparatus according to claim 1, wherein the signal processing unit selects a reception beam located at the center of the orthogonal coordinate mesh. Radar used in a radar apparatus including an antenna unit that forms a plurality of radar beams in an elevation angle direction from a plurality of antenna elements, transmits radio waves by sequentially changing the azimuth direction, and receives reflected waves from a weather target A signal processing method comprising:
Forming a plurality of reception beams by the reception signal of the reflected wave;
The received beam is mapped from a three-dimensional polar coordinate mesh to a three-dimensional orthogonal coordinate mesh, and when the orthogonal coordinate mesh includes a plurality of received beams, one received beam is selected , and the selected received beam is selected. A radar signal processing method characterized in that beam synthesis is performed based on a signal and received data in an orthogonal coordinate system is output. 5. The radar signal processing method according to claim 4, wherein a reception beam having the largest ratio to the orthogonal coordinate mesh is selected. 5. The radar signal processing method according to claim 4, wherein a reception beam located at the center of the orthogonal coordinate mesh is selected.

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