Airborne Ka-Band Probe Radar-Radiometer (KPR)

KPR is a compact Ka-band Probe Radar and radiometer for measuring vertical profiles of reflectivity and Doppler velocity. Key features of the instrument are: a pair of flat-plate array antennas pointing in the zenith and nadir directions, 10 W peak power solid state transmitter amplifier and a low-loss switch network. KPR includes an integrated noise source and ambient load for sky brightness temperature measurements and radiometric calibration of its receiver. The instrument is packaged to install in a standard (6″ ID x 24″ L) PMS probe canister. KPR is also available as a dual-polarized radar with a single antenna in either zenith, nadir, or forward looking configuration.

KPR is packaged to operate from a custom wired, but mechanically standard PMS probe canister. The first test flights were conducted on-board the Univ. of Wyoming KingAir research aircraft in January 2016.

KPR is packaged to operate from a custom wired, but mechanically standard PMS probe canister. The first test flights were conducted on-board the Univ. of Wyoming KingAir research aircraft in January 2016.

EXAMPLE DATA:

kpr-20160904-155458_ref

kpr-20160904-155458_vel

kpr-20160904-155458_sw

Combined short pulse – chirped long pulse reflectivity (top), Doppler velocity (middle) and Doppler velocity spectrum width (bottom – uncorrected for aircraft motion) images collected on September 4, 2016 near Laramie Wyoming from the Univ. of Wyoming King Air research aircraft. The aircraft was flying approximately 3 km above ground and 2 km above the melting layer, while collecting data using alternating pulse pairs from the zenith and nadir pointing antennas at 30 m range resolution.

SPECIFICATIONS:
Frequency:   35.6 GHz
Transmitter:   10 W solid state power amplifier
Antennas:   14 cm flat-plate array, 4.5 deg. beam-width
Pulsing:   Interleaved short RF and linear FM pulses
Range Resolution:   30, 75, 100 or 150 m
Delta T:   1 K @ 200 ms integration (5 Hz data rate)
Rec. Noise Temp.:   440 K
Radomes:   Matched Rexolite window
Weight:   25 lb (40 lb with canister)
Power:   50 W AC; 100 W  28 VDC
 –
SENSITIVITY:
KPR Sensitivity
KPR unity signal to equivalent noise ratio sensitivity in clear air and 0.1 second integration for 30 and 150 m range resolution. Short RF pulse is used close to the radar and a 10x longer chirped pulse is used at farther ranges.