Instrument : X-Band Scanning ARM Precipitation Radar (XSAPR)
The X-band scanning ARM precipitation radar (X-SAPR) is an X-band dual-polarization Doppler weather radar manufactured by Radtec, Inc. The X-SAPR operates in a simultaneous transmit and receive (STAR) mode, meaning that the transmit signal is split so that power is transmitted on both horizontal and vertical polarizations at the same time. The X-SAPR transmitter is a 200 kW (peak power) magnetron. The receiver is based upon the Vaisala RVP-900 and runs Vaisala’s IRIS software. In addition to the first three Doppler moments (reflectivity, radial velocity, and spectra width), the X-SAPR also provides differential reflectivity, correlation coefficient, and specific differential phases. The dual-polarization variables will allow the provision to provide estimates of rainfall rates and identification of precipitation types. At the Southern Great Plains, there are three X-SAPRs surrounding the Central Facility, providing the capability to use multi-Doppler velocity retrievals to estimate wind fields.
The X-SAPR represents a new measurement capability for ARM.
- xsaprhsrhi : X-SAPR Horizon-to-horizon Range-Height Indicator scan
- xsaprppi : X-SAPR Plan Position Indicator scan
- xsaprsur : X-SAPR Surveillance scan
- xsaprvad : X-SAPR Velocity-Azimuth Display scan
- xsaprvpt : X-SAPR Vertical PoinTing scan
The following measurements are those considered scientifically relevant.
Iosif (Andrei) Lindenmaier