Micro- Rain- Radar
Local Area Weather Radar
Cloud Radar
Gerhard Peters
Meteorological Institute University Hamburg
COPS-GOP-WS3 Hohenheim 2006_04_10
MRR (Micro Rain Radar) characteristics
Radar Wavelength
=1.25 cm
Transmit Power
50 mW
Modulation
FM-CW
Beam width (2 way 6 dB)
2°
Antenna
Offset parabola
Number of range gates
31
Time Resolution
10 s
Spectral Velocity Resolution
0.191 m/s
Nyquist Velocity Range
0-12.3 m/s
Number of power spectra in 1 s
25
Min. detectable radar reflectivity
(z=1000 m, dz=100 m, dt=60 s)
-2 dBZ
COPS-GOP-WS3 Hohenheim 2006_04_10
Zingst, 1999-06-11, 100 m
10
4
11:10
11:11
11:12
3
spectral radar reflectivity [mm
6
3
/m /(m/s)]
10
10
10
10
10
2
1
0
-1
0
2
4
6
fall speed [m/s]
COPS-GOP-WS3 Hohenheim 2006_04_10
8
10
12
Zingst, 1999-06-11, 100 m
10
5
11:10
11:11
11:12
4
spectral radar reflectivity [mm
6
4
/m /mm]
10
10
10
10
10
3
2
1
0
0
0.5
1
1.5
2
2.5
3
drop diameter [mm]
COPS-GOP-WS3 Hohenheim 2006_04_10
3.5
4
4.5
5
5.5
0.4
11:10
11:11
11:12
M-P, 4.9 mm/h
3
lwc(D) [g/m /mm]
0.3
0.2
0.1
0
0
1
2
3
D [mm]
COPS-GOP-WS3 Hohenheim 2006_04_10
4
5
5
11:10
11:11
11:12
M-P, 4.9 mm/h
rr(D) [mm/h/mm]
4
3
2
1
0
0
1
2
3
D [mm]
COPS-GOP-WS3 Hohenheim 2006_04_10
4
5
/mm]
-3
N(D) [m
10
4
10
3
10
2
10
1
10
0
10
-1
10
-2
10
-3
10
-4
11:10
11:11
11:12
M-P, 4.9 mm/h
0
1
2
3
D [mm]
COPS-GOP-WS3 Hohenheim 2006_04_10
4
5
COPS-GOP-WS3 Hohenheim 2006_04_10
Zingst, Apr 16, 1998 06:45 UTC
height [m]
1500
1000
500
0
2
4
6
8
fall speed [m/s]
10
26 28 30
Ze[dbZ]
COPS-GOP-WS3 Hohenheim 2006_04_10
0 2 4 6 8 0
vm[m/s]
10
20
R [mm/h]
Spectral Modes
Top: Time-diameter cross section of slope of spectral rainrate  2 R / D 2
The red lines
indicate
spectral
maxima
The red lines
indicate
height of
melting layer
Bottom: Time-height cross section of rain rate
COPS-GOP-WS3 Hohenheim 2006_04_10
Integral Modes
1 spectral maximum
2 spectral maxima
COPS-GOP-WS3 Hohenheim 2006_04_10
LAWR characteristics
Based on Nautical Radar Furuno, Type FR7112
Fan-beam-antenna replaced by pencil beam (Offset Parabol, 85 cm)
Polarization:
Horizontal
Scan Rate:
24 rpm
X-Band Transceiver:
Fixed to Antenna Unit
Transmit power:
12 kW peak
Frequency:
9410 ± 30 MHz (X-Band)
Pulse width, Pulse repetition rate
0.08 µs/2100 Hz
0.3 µs/1200 Hz
0.8 µs/600 Hz
Sampling Rate
10 MHz (corresponds to 15 m range resolution)
Digital power resolution
0.005 dB
Dynamic range
70 dB
Beam width
2.5 ° (3dB 1 way)
Antenna Gain
> 30 dBi
Beam Elevation:
+3° to + 20° (adjustable).
Sensitivity:
0 dBZ, (5 km range, 0.08 µs pulse width, 30 s time integration, 60 m
range integration, 2° azimuth integration)
COPS-GOP-WS3 Hohenheim 2006_04_10
LAWR characteristics
COPS-GOP-WS3 Hohenheim 2006_04_10
Proposed radar sites
LAWR
14
MRR
sites
COPS-GOP-WS3 Hohenheim 2006_04_10
What is a Cloud Radar?
40
10
4
30
20
10 3
dBZ
10
weather radar
0
10 2
cloud radar
-10
-20
10 1
-30
-40
10 0
-50
0.001
0.01
0.1
LWC gm^-3
COPS-GOP-WS3 Hohenheim 2006_04_10
1
10
Cloud Radar MIRA 36 characteristics
COPS-GOP-WS3 Hohenheim 2006_04_10
Cloud Radar MIRA 36 measurement characteristics
Minimum Height
200 m
Measuring Range
15 km
Range Resolution
15, 30, 45, and 60
m
Doppler Velocity Resolution
0.05 m/sec
Maximum Unambiguous Velocity
±15 m/sec
Number of Gates (max)
500
FFT Length
128, 256, and 512
Minimum Dwell Time
0.1 sec
Antenna Beam Width
0.6 deg. X
deg.
Number of Gates with Simultaneously Stored 8
Raw Data (max)
Sensitivity at 5 km (the integration time of 0.1 -41 dBZ
sec.)
COPS-GOP-WS3 Hohenheim 2006_04_10
0.6
Cloud Radar MIRA 36 technical characteristics
Frequency
36.5 +/- 0.5 GHz
Peak Power (max)
30 kW
Tube Type
magnetron
Pulse Width
100-400 ns
Pulse Repetition Frequency
2.5, 5, and 7.5 kHz
Minimum Detectable Signal
-104 dBm
Sampling Rate
50 MHz
Sampling Resolution
12 bit
Type of Bus for the Signal Processing Board
PCI
Operation System of the Host Computer
Linux or Windows
Network Protocol
TCP/IP
Antenna Diameter
1m
Sidelobe Level
-20 dB
Power Supply
230V+/-10% AC
Power Consumption (max)
1.3 kW
Weight
140 kg
COPS-GOP-WS3 Hohenheim 2006_04_10
Cloud radar Products
Elmshorn 2006-10-01
Elmshorn 2006-10-01
Reflectivity
Linear Depolarization
Ratio
Mean Doppler Velocity
No Precipitation
COPS-GOP-WS3 Hohenheim 2006_04_10
Drizzle
Cloud radar Products
Geesthacht 2000-09-06 12:52
COPS-GOP-WS3 Hohenheim 2006_04_10
Cloud radar Products
Geesthacht 2000-09-04 21:09
COPS-GOP-WS3 Hohenheim 2006_04_10
Cloud radar radar site?
COPS-GOP-WS3 Hohenheim 2006_04_10