====== W-Band Cloud radar (JOYRAD-94) ====== {{:wiki:instruments:joyrad94.jpg?direct&600|JOYCE-JOYRAD94 ©N. Küchler}} \\ //Cloud radar JOYRAD-94 installed at Jülich// ===== Principle ===== 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 {{ :joyce_data_request_form.pdf |data request sheet}} and send it to [[mailto:info@joyce.cloud|info@joyce.cloud]] ^ Dataset ^ Temporal resolution ^ File size ^ Filename ^ Remarks ^ | Radar moments, Liquid water path | 5 seconds | 1 file per hour (8-12 MB) | //mirac_jue_-a_YYYYMMDDHHMMSS_P01_ZEN_compact.nc// | | ===== Composite products using W-Band radar data ===== * **Dual-wavelength ratio** Ka/W-Band [[http://gop.meteo.uni-koeln.de/~Hatpro/dataBrowser/dataBrowser2.html?site=TRIPEX-pol&date=-1&UpperLeft=3radar_Ze&UpperRight=3radar_DWR|Link to Quicklooks]] ===== Link to current observations ===== Data quicklooks can be found in the [[https://atmos.meteo.uni-koeln.de/~lpfitzen/dataBrowser/dataBrowser2.html?site=Mirac-A&date=-1&UpperLeft=Mirac-A_radar_overview&UpperRight=Mirac-A_radar_status|JOYCE quicklook archive]] ===== Measurement examples ===== {{wiki:examples:20191211_mirac-a_moments_overview.png?direct&500|JOYRAD-94_obs}} //Example time series of MiRAC-A observations at JOYCE (radar moments / LWP)// ===== JOYRAD-94 History ===== ^ Period ^ Place ^ Project ^ | 14/06/2019 - today | [[http://www.awipev.eu/|AWIPEV at Ny-Ålesund]], Norway | (AC)3 | | 23/03/2018 - 06/03/2019 | [[http://gop.meteo.uni-koeln.de/ag_crewell/doku.php?id=sites:iquique|Iquique]], Chile | [[http://sfb1211.uni-koeln.de/|CRC1211]] | | 10/06/2016 - 26/07/2017 | [[http://www.awipev.eu/|AWIPEV at Ny-Ålesund]], Norway | (AC)3 | | 16/10/2015 - 23/03/2016 | [[http://www.fz-juelich.de/|Research Center Jülich]], Germany | JOYCE | ===== MiRAC-A History ===== ^ Period ^ Device ^ Place ^ Project ^ | 11/12/2020 - today | MiRAC-A | [[http://www.fz-juelich.de/|Research Center Jülich]], Germany | JOYCE | | 08/2020 - 09/2020 | MiRAC-A | Polar 5, Svalbard | | | 31/05/2019 - 08/01/2020 | MiRAC-A | [[http://www.fz-juelich.de/|Research Center Jülich]], Germany | JOYCE | | 03/2019 - 04/2019 | MiRAC-A & -P | Polar 5, [[http://www.ac3-tr.de/overview/observations/aflux-2019/|AFLUX campaign]], Svalbard | [[http://www.ac3-tr.de/|(AC)3]] | | 28/07/2017 - 08/10/2018 | MiRAC-A & -P | [[http://www.awipev.eu/|AWIPEV Ny-Ålesund]], Svalbard | [[http://www.ac3-tr.de/|(AC)3]] | | 05/2017 - 07/2017 | MiRAC-A & -P | Polar 5, [[http://www.ac3-tr.de/news/acloud-campaign/|ACLOUD campaign]], Svalbard | [[http://www.ac3-tr.de/|(AC)3]] | {{:wiki:instruments:mirac_a_nya.jpg?direct&600|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 | for integral liquid water (LWP) detection (2 GHz BW) | 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 | [[http://www.radiometer-physics.de/|RPG]] |