Ka-band Solid-State Doppler Polarimetric Cloud Radar

A Ka-band Doppler polarimetric cloud radar is outfitted with a 20 W GaN solid-state power amplifier. The radar has been developed on the basis of its magnetron-based predecessor (http://radar.kharkov.com/index.php?s=3&p=29&n=75) in the course of movement toward all solid-state low-cost, compact millimeter wave cloud radars. The upgrade has been made through replacing a transmitter alone and adding some extra routines in the digital signal processor to implement the pulse compression technique. The radar sensitivity no worse than -28 dBZ at 5 km is achieved.


Radar essential characteristics

Frequency Range 35000 … 35200 MHz
Peak Output Power 20 W
Pulse Duration 0.1 … 100 µs
Maximum Duty Cycle up to 100%
Maximum PRR 20 kHz
Receiver Noise Figure 3.5 dB
Losses Tx/Rx 0.5/2 dB
Antenna Diameter 0.5 m
Antenna Gain 43 dB
Antenna Beamwidth 1.2°
Polarization Cross-Isolation > 35 dB
SNR of the power spectra obtained by Doppler processing >75 dB
Number of Range Bins 1000
Dimensions 435×380×300 mm3
Weight 30 kg
Cooling Natural convection
Temperature Range -40 … +60 °C
Supply Voltage AC, 90 … 250 V, 50/60 Hz
Radar products signal-to-noise ratio, linear depolarization ratio, 1-st and 2-nd moments of the Doppler spectrum for each range bin   full Doppler spectrum data for both co- and cross-components for a chosen bin


Radar operational modes

Mode Pulse width, µs PRF, Hz Range bin, m Blind/Max range, m Min dBZ @km
SSPA Magnetron
Short 0.48 14000 72 200/8000 -29 -42 1
Middle 6 9000 36 1000/15000 -28 -32 3
Far 20 7000 36 3100/17000 -28 -27 5


Radar operation example

Weather conditions: light-to-moderate snowing condition at the outside temperature close to zero.  

Fig.1 Range reflectivity profile snapshot and 5 minute time evolution map


Fig.2 LDR range profile snapshot and 5 minute time evolution map