User Tools

Site Tools


W-Band Cloud radar (JOYRAD-94)

JOYCE-JOYRAD94 ©N. Küchler
Cloud radar JOYRAD-94 installed at Jülich


The W-Band cloud radar is a Frequency Modulated Continuous Wave (FMCW) Radar that transmits saw tooth frequency chirps at 94 GHz. In this way, vertical profiles of reflectivity, Doppler velocity, Doppler spectral width are detected from 150 m to 10 km above ground. Given these measurements, information on the macrophysical (cloud boundaries, type of cloud particles) and microphysical (e.g., liquid and ice water content) properties of the detected cloud can be derived. The radar is operated in a vertically pointing mode. Additionally, the system is equipped with a passive radiometric channel at 89 GHz that is sensible to cloud liquid water. Passive and active receivers are fed by the same antenna, i.e. a perfect beam overlap is accomplished.

Measurement modes

  • Vertically pointing observations with integration times up to 1 seconds, variable chirp-tables possible (Doppler resolution, range resolution)

JOYCE-CF Standard Operation Procedures

  • Standard measurement mode is vertically pointing, 5 seconds integration time

Calibrations and data quality assurance procedures

  • Check with co-located disdrometer to find out reflectivity offsets
  • Consistency check with other cloud radars

Data availability

Data are available via request please fill the data request sheet and send it to

Dataset Temporal resolution File size Filename Remarks
Radar moments, Liquid water path 5 seconds 1 file per hour (8-12 MB)

Composite products using W-Band radar data

Data quicklooks can be found in the JOYCE quicklook archive

Measurement examples


Example time series of MiRAC-A observations at JOYCE (radar moments / LWP)

JOYRAD-94 History

Period Place Project
14/06/2019 - today AWIPEV at Ny-Ålesund, Norway (AC)3
23/03/2018 - 06/03/2019 Iquique, Chile CRC1211
10/06/2016 - 26/07/2017 AWIPEV at Ny-Ålesund, Norway (AC)3
16/10/2015 - 23/03/2016 Research Center Jülich, Germany JOYCE

MiRAC-A History

Period Device Place Project
11/12/2020 - today MiRAC-A Research Center Jülich, Germany JOYCE
08/2020 - 09/2020 MiRAC-A Polar 5, Svalbard
31/05/2019 - 08/01/2020 MiRAC-A Research Center Jülich, Germany JOYCE
03/2019 - 04/2019 MiRAC-A & -P Polar 5, AFLUX campaign, Svalbard (AC)3
28/07/2017 - 08/10/2018 MiRAC-A & -P AWIPEV Ny-Ålesund, Svalbard (AC)3
05/2017 - 07/2017 MiRAC-A & -P Polar 5, ACLOUD campaign, Svalbard (AC)3

MiRAC-A ©B. Pospichal
MiRAC-A installed at Ny-Ålesund

Technical Specifications

Parameter Specification Remark
Frequency 94 GHz ± 100 MHz corresponds to wavelength of 3.19 mm; adjustable by software between 92.3 and 95.7 GHz
IF Range 350 kHz to 3 MHz
Transmitter Power ~ 2 W solid state amplifier
Antenna gain 51.6 dB
Beam Width 0.48° FWHM
Polarisation V
System Noise Figure 3 dB
Dynamic Range -54 dBZe to +20 DBZe at 1km height, -45 dBZe to +20 dBZe at 3 km height, -36 dBZe to +20 dBZe at 10 km height
Ranging 50 m to 18 km
Calibration Transmitter power monitoring, Receiver Dicke switch (for radar and DD channels), Hot/Cold absolute receiver calibration Accuracy 0.4 dB
A/D Sampling Rate 8.2 MHz
Profile Sampling Rate 0.2 s to 30 s
Vertical Resolution 1 m to 100 m (user selectable)
Doppler Resolution ± 1.5 cm/s
Doppler Range ± 18 m/s max.
Chirp Variations 4 typical 10 possible, re-programmable
Passive Channels 89 GHz
Data Products Reflectivity, Doppler-velocity, Spectral Width, Higher Moments, Doppler Spectra, LWC profiles
Data Formats proprietary binary, netCDF (conformity with CF convention), ASCII (only moment profiles)
Rain / Snow Mitigation System Super blower for rec. / transm. radome (2000 m³/h each) Optional heater modules (2 kW to 4 kW)
Weight Radar main body: 100 kg, Table: 130 kg, Air conductors: 25 kg
Power Consumption 220 V AC, 50-60 Hz, Radar: 400 W, Blowers: 1000 W
Manufacturer RPG
wband.txt · Last modified: 2021/04/01 17:07 by bpospich