Design of an UltraStable 3 Frequency Dual Pol

Design of an Ultra-Stable 3 Frequency / Dual Pol. Radiometer for Remote Sensing of Rain T. Rose (RPG), H. Czekala (RPG), Soil Moisture Instrument (BNU Beijing) COPS Campaign (Black Forest / Germany) RPG Radiometer Physics Gmb. H RPG‘s Polarized Radiometers

RPG’s Dual Polarized Radiometer Versions 6. 925 / 10. 65 / 18. 7 / 36. 5 GHz Soil Moisture Radiometer RPG Radiometer Physics Gmb. H 10. 65 / 21. 0 / 36. 5 GHz Rain Observation Radiometer RPG‘s Polarized Radiometers

Rain Observation Radiometer RPG-6 CH-DP 10. 65 GHz: high rain rates >30 mm/h 21. 00 GHz: med. rain rates >10 mm/h 36. 5 GHz: drizzle Discrimination of cloud liquid and rain liquid water due to polarized emission from rain droplets RPG Radiometer Physics Gmb. H RPG‘s Polarized Radiometers

Dicke Switch / Noise Injection Calibration System Modular Direct Detection Filterbank Design: • High long term stability due to full auto-calibrating front end • Parallel data aquisition of all channels RPG Radiometer Physics Gmb. H RPG‘s Polarized Radiometers

Waveguide DDFB Design Full waveguide design guarantees high mechanical stability Receiver Noise Temperature: < 400 K Auto-Calibration Devices: Noise Injection Magnetically switched Dicke SW RPG Radiometer Physics Gmb. H RPG‘s Polarized Radiometers

Y-Junction Isolator Dicke Switch Design RPG Radiometer Physics Gmb. H RPG‘s Polarized Radiometers

Y-Junction Isolator Dicke Switch for 90 GHz RPG Radiometer Physics Gmb. H RPG‘s Polarized Radiometers

RPG Waveguide Dicke Switches RPG Radiometer Physics Gmb. H RPG‘s Polarized Radiometers

Calibration Timing RPG Radiometer Physics Gmb. H RPG‘s Polarized Radiometers

Other Receiver Examples 90 / 150 GHz • full internal cal. • Insertion loss 90 GHz DS: 0. 7 d. B Insertion Loss 150 GHz DS: 1. 0 d. B Isolaton >30 d. B RPG Radiometer Physics Gmb. H RPG‘s Polarized Radiometers

Calibration Test of Principle with 21 / 36. 5 GHz System 12 Hours RPG Radiometer Physics Gmb. H RPG‘s Polarized Radiometers

Power Spectrum RPG Radiometer Physics Gmb. H RPG‘s Polarized Radiometers

Allan Variance up to 4000 Seconds RPG Radiometer Physics Gmb. H RPG‘s Polarized Radiometers

Thermal Receiver Stability Hermetically insulated receivers Thermal Stability <30 m. K over full operating temp. range (-30°C to +45 °C) • Dual stage thermal control system • Peltier stabilized receiver board • Low receiver power consumption < 3 Watts RPG Radiometer Physics Gmb. H RPG‘s Polarized Radiometers