HCR Request Guidance


The NCAR HIAPER Cloud Radar (HCR) is an airborne millimeter (W-band) wavelength radar that provides high spatial and temporal resolution remote sensing capabilities on the NSF/NCAR HIAPER aircraft. The HCR is housed in a 20 inch diameter wing pod and is capable of estimating winds and microphysics over a 15 km radius with 40 meter gate spacing. HCR can be operated in scanning and fixed-pointing modes for detecting cloud boundaries and cloud liquid and ice. The HCR beamwidth is 0.7 deg and range resolution is between 40 and 150 m.

Configuration: NSF/NCAR HIAPER GV aircraft
Number of available systems: 1


Science: Dr. Ulrike Romatschke / romatsch@ucar.edu / (303) 497-8817
Data: eol-datahelp@ucar.edu

HIAPER Cloud Radar (HCR) Facility Request Guidance Information
Parameter Specification
Antenna 0.3 m, lens
Antenna gain 45.7 dBi
Beamwidth 0.73 deg
Transmit frequency 94.4 GHz
Transmit wavelength 3.2 mm
Transmitter Klystron
Peak transmit power 1.6 kW
Pulse width 0.2 - 1.0 μs
Pulse repetition frequency (PRT) up to 10 kHz
Range resolution 20-180 m
Unambiguous range 15 km, PRF=10kHz
Receiver bandwidth 20 MHz
Receiver noise figure 8.9 dB
Sensitivity -37.0 dBZ at SNR=-10dB, 1 km, and 256 ns pulse
Typical reflectivity uncertainty 1-2 dB
Unambiguous velocity +/- 7.75 m/sec, PRF=10kHz
Typical radial velocity uncertainty 0.2 m/s at W=2 m/s
Typical dwell time 100 ms


Typical data variables
Variable Dimension Unit Dimension
time time s Seconds since volume start
range range m Range from instrument to center of gate
elevation time deg Ray elevation angle
DBZ n_points dBZ Reflectivity
VEL n_points m/s Doppler velocity
WIDTH n_points m/s Spectrum width
LDR n_points dB Linear depolarization ratio
MELTING_LAYER n_points   Melting layer flag
CONVECTIVITY n_points   Convectivity (from 0 [stratiform] to 1 [convective])
ECHO_TYPE n_points   Convective/stratiform echo type
PID n_points   Hydrometeor particle ID
PRESS n_points hPa ERA5 pressure
TEMP n_points C ERA5 temperature
RH n_points % ERA5 relative humidity