Ka-Band Zenith Radar (KAZR)

KAZR is an upward-looking cloud radar operating at 34.8 GHz. KAZR has a four channel receiver, providing simultaneous reception of short pulse and chirp waveforms on co-polarized and cross polarized channels.

The KAZR antenna is mounted on top of the shelter with a short waveguide connection between the antenna and RF unit. The shelter is a customized sea container which makes the system easily transportable to different experiment sites. The custom sea container is approved for international shipping.

KAZR systems have been deployed at US Department of Energy Atmospheric Radiation Measurement (ARM) permanent sites in Oklahoma, Alaska, Azores, and at mobile sites around the world, including Antartica and the Amazon. In 2013, ProSensing installed a KAZR system at Lanzhou University’s remote weather monitoring site in Central China.

KAZR Features
  • Simultaneous transmission of short pulse (for clouds from 200m-2 km altitude) and chirp mode (for clouds from 2-17.5 km altitude)
  • Transmitter alternates between full power and reduced power modes to avoid saturation in heavy rain
  • Temperature stabilized RF unit
  • Arbitrary waveform generator (ARB) capable of generating any user-defined waveform of up to 16K samples in length. The ARB can generate linear FM, non-linear FM, binary phase-coded, or any arbitrary waveform up to approximately 50 microseconds duration
  • High power EIK transmitter with accurate single pulse peak power monitoring system
  •  Four-channel 16-bit digital receiver for simultaneous reception of four waveforms
    • short pulse co-polarized
    • chirp pulse, co-polarized
    • short pulse, cross-polarized
    • chirp, cross-polarized
  • Continuous monitoring of system temperatures, voltages, humidity and data system
  • Webpage for system monitoring and quick-look data display
KAZR Specifications

RF output frequency: 34.83 GHz (short pulse mode) 34.89 GHz (chirp mode)

Peak transmit power: 2.0 kW

Transmitter duty cycle: 5% max

Pulse widths (selectable): 50-13000 ns

Transmit polarization: Linear polarization

Receiver polarization: Single receiver switched between co-polarized and cross-polarized reception

LNA noise figure: 2.8 dB, typical

IF output to digital receiver: 90 MHz / 150 MHz

Antenna Diameter: 1.82 m (72″)

Antenna Gain: 53 dBi typical

Antenna Beamwidth: .33 degrees

Cross-polarization isolation: -25 dB typical

First sidelobe level: -18 dBi typical (-16 dBi min)

 

Typical Data

Quick look files available on KAZR web page, showing reflectivity in four operating modes

Group A (full power)                                            Group B (low power)

reflecitivity quick looks

Linear Depolarization Ratio (LDR).

Data in light rain below 3 km shows 30 dB cross-polarization isolation

Group A (full power)                                            Group B (low power)

LDR_quick_looks

 

KAZR installed at Lanzhou University's remote weather monitoring site in Central China