Transcript O5_02_Mizutani

Development of Active Phased Array Weather Radar
Masakazu Wada
© 2012 Toshiba Corporation
Comparison of Dual-Pol and Phased-array Radar
Parabolic radar
Phased Array Weather Radar
Dual-Pol Radar
PAWR
(phased array antenna)
（parabolic antenna）
Elevation: Mechanical
Azimuth: Mechanical
About 20
／5 to10 minutes
Zh，Vh，Wh，Zdr，Kdp，ρhv
Scanning
Elevation Number
／Time Interval
Parameter
Elevation: Electronic
Azimuth: Mechanical
About 100
／10 to 30 seconds
Zh，Vh，Wh
Development of Active Phased Array Weather Radar
© 2011 Toshiba Corporation
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Concept on Phased-array Radar
About 2m
About 2m
Overview of Antenna
＜Cost Performance＞
•1-dimension Active Phased
Array Antenna and DBF（Digital
Beam Forming)
•Maximize the Cost Performance
•The same price range as
compared to parabolic radar
Overview of Antenna Scan
＜Antenna Scan＞
•1 degree of azimuth beam width
by slotted antenna mechanically
•1 degree of elevation beam width
by Antenna electronically
•Fan beam transmission
•Multi-beams receiving by DBF
•3D fast observation with one
rotation
Development of Active Phased Array Weather Radar
© 2011 Toshiba Corporation
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Block Diagram
DBF output
(16 beams)
DBF
……………..
A/D and I/Q
(128 lines)
……………..
Rx Frequency Conversion
(128 lines)
…………
Receiver
(96 lines)
…………
No DBF output
(128 I/Q data)
I/Q Data Accumulation
(for study)
..
…
Transmitter and
Receiver
(24 lines)
…
Slotted Waveguide antenna (128 elements)
Digital Signal Processor
•Pulse Compression
•Calculate
Radar Reflectivity
Doppler Velocity
Velocity Width
Tx Frequency
Conversion
Use
Gallium Nitride
on Tx Amp
D/A
～
Digital
Seed
Development of Active Phased Array Weather Radar
© 2011 Toshiba Corporation
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Active Phased Array Antenna
2.1m
2.2m
Active Phased Array Antenna
Development of Active Phased Array Weather Radar
© 2011 Toshiba Corporation
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Tx/Rx Unit
Condenser
card
Tx/Rx
Card
Frequency
Conversion
Card
Include 8ch Tx/Rx Elements The system uses 3 units
Development of Active Phased Array Weather Radar
© 2011 Toshiba Corporation
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Receiving Unit
Rx
Card
Frequency
Conversion
Card
Include 8ch Rx Elements The system uses 13 units
Development of Active Phased Array Weather Radar
© 2011 Toshiba Corporation
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Frequency Conversion Card
Development of Active Phased Array Weather Radar
© 2011 Toshiba Corporation
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A/D I/Q Unit
16ch A/D & I/Q The system uses 8 units
Development of Active Phased Array Weather Radar
© 2011 Toshiba Corporation
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DBF Unit
The system uses DBF technique
to calculate beam form from 128 I/Q data
Development of Active Phased Array Weather Radar
© 2011 Toshiba Corporation
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Observation Mode
Specification
Maximum
Up to 430W
Power
Frequency
Beam Width
(after DBF)
Mode
Coverage
Scan
Interval
Number of
Hit
Number of
Elevation
9320 to 9445MHz, 5MHz step
About 1 degree
Fast
Wide
Observation
Observation
20㎞
60㎞
10 seconds
30 seconds
About 10
About 20
About 100
About 100
Prepare wide observation mode and fast obsevation mode
Development of Active Phased Array Weather Radar
© 2011 Toshiba Corporation
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Phased-array Radar installed in Osaka Univ.
Active Phased
Array Antenna
Left: Radar
Processor
Right: Radar
Controller
Active Phased Array Weather Radar installed in Osaka Univ.
Development of Active Phased Array Weather Radar
© 2011 Toshiba Corporation
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Conclusion
• Active Phased-array Weather Radar is able to generate
3D data without any gap in the period of 10 to
30seconds, in order to capture cumulonimbus quickly.
• We have installed Active Phased-array Radar on Osaka
urban area and are evaluating it now.
• To protect safety of critically significant infrastructure
such as urban area and Airport from disaster, Toshiba
propose multiple observation using dual-pol solidstate radar and 1D phased-array radar.
This research is supported by
the National Institute of Information and Communications Technology, Japan.
Development of Active Phased Array Weather Radar
© 2011 Toshiba Corporation
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Toshiba’s Presentations in the Exhibition
 Exhibitor Booth
<No. 5005>
Right in front of main entrance
© 2011 Toshiba Corporation
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Development of Active Phased Array Weather Radar
© 2011 Toshiba Corporation
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Measurement ( Anechoic Chamber )
We have one of the largest Chamber in Eastern Japan.
Development of Active Phased Array Weather Radar
© 2011 Toshiba Corporation
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NSI Receiver
Amplitude
Phase
Near field data
Azimuth
Amplitude [dB]
10
0
-10
-20
-30
-40
-80
-60
-40
-20
0
20
40
60
80
20
40
60
80
Azimuth [deg]
Elevation
Amplitude [dB]
10
0
-10
-20
-30
-40
-80
-60
-40
-20
0
Elevation [deg]
Calculated far field pattern
Development of Active Phased Array Weather Radar
© 2011 Toshiba Corporation
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Antenna Pattern ( Azimuth)
Antenna Pattern (Azimuth)
0
Amplitude[dB]
-10
-20
＜Beam Width＞
1degree or less
<Side lobe>
-23dB or less
-30
-40
-50
-80
-60
-40
-20
0
20
40
60
80
Azimuth [deg]
Mechanical Beam Forming by Slot Antenna
Development of Active Phased Array Weather Radar
© 2011 Toshiba Corporation
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Transmission and Receiving Pattern ( Elevation)
Transmission and Reception (Multi Beam) Pattern
TX_8element
Rx_EL5deg
Rx_EL0deg
Rx_EL-1deg
Rx_EL1deg
Rx_EL-2deg
Rx_EL3deg
Rx_EL-4deg
Rx_EL2deg
Rx_EL-3deg
＜Beam Width＞
1degree (Rx)
<Side lobe>
-10dB or less (Tx)
-23dB or less (Rx)
0
-10
Amplitude[dB]
Rx_EL4deg
Rx_EL-5deg
-20
-30
-40
-50
-45
-30
-15
0
Elevation[deg]
15
30
45
1 transmission beam and receiving multi beam by DBF
Electronic Scan EL 0deg to 90 deg
Development of Active Phased Array Weather Radar
© 2011 Toshiba Corporation
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Forecast of potential
Maturation
Forcast at this
Strong rainfall
Life cycle of Cumulonimbus
Vertical Integrated Liquid (VIL) and by the vertical distribution of precipitation, it
is possible to predict the precipitation may fall to the ground
in the near future
© 2011 Toshiba Corporation
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Pulse Compression Technique
Transmission power can be reduced compared with conventional radar systems on a detection-range
basis.
>> Reduction in operating voltage of the transmitter circuits
>> Downsizing of the transmitter
>> Suppression of the level of interference wave, etc.
Transmitted
Waveform
Klystron
Solid-state Pulse
Compression Radar
Chirp modulation ( Frequency modulation )
2)
3)
4)
Delay time
1)
2) transmit this linear FM pulse
4) collect the divided frequency power in the received pulse
Amplifier
1) add the frequency modulation on the transmission pulse
3) put the received signal through the time delay filter
Frequency
Development of Active Phased Array Weather Radar
time
10/20/2011
© 2011 Toshiba Corporation
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