The cloud radar MIRA36-S is a mobile, dual-polarization Doppler radar with a wavelength of 8.5 mm (35.5 GHz). It has a scanning Cassegrain antenna that allows to cover the area above 45 degrees elevation over all azimuth angles. The scanner covers the azimuth with a small overlap at each end from -3 … 363 deg. as continuous rotation into one direction is not possible due to mechanical limitations. The strength of the MIRA36-S is its high sensitivity. With a pulse repetition frequency of 5 kHz, a pulse duration of 200 ns and an averaging time of 0.1 s, it can detect a -44 dBz echo at a distance of 5 km. Mounted on a car trailer, the radar can be moved easily. For intercontinental transports the radar system fits into a ISO 1496 20’ HC sea container.

Fig.1: MIRA36-S cloud radar (Metek Comp., Elmshorn, Germany) Fig.2:MIRA36-S cloud radar, in field campaign.
                                      Fig.3: Measurment of Z, w and LDR.

Technical specifications:

Radar type: monostatic, pulsed, magnetron
Transmitting frequency: 35.5 GHz ± 0.2 GHz
Peak power: 30 kW
Duty cycle: max 1:500; typically 1:1000
Pulse duration: 100 ns, 200 ns and 400 ns, corresponding to 15 m, 30 m and 60 m resolution
Minimum measuring distance: 150 m, -6 dB sensitivity above 300 m, -1.5 dB sensitivity above 400 m, full sensitivity above 500 m
Maximum range: 500 Rangegates, corresponding to 15 km / 30 m
Resolution of the Doppler speed: 0.02 ms-1
Pulse Rate (PRF): 2.5 kHz, 5kHz or 10 kHz, corresponding to a maximum unique speed of 11 to 42 ms-1
FFT length: 128, 256, 512, 1024
Minimum averaging interval: Instantaneous spectra moments can be evaluated without gaps if the number of FFT points is greater than 128.
Signal sampling (ADC): 50 MHz / 14 bits
Antenna construction: Cassegrain
Antenna diameter: 1.2 m
Antenna beam width (6 dB / two-way): 0.52 deg. x 0.52 deg.
Antenna gain: 50.4 dBi
Polarization separation: -35 dB
Antenna positioning accuracy: 0.1 deg.
Scan range azimuthal: -183 deg. ... + 183 deg.
                    elevational: -45 deg. ... + 45 deg.
Maximum scanning speed, both directions: 10 deg. s-1
Maximum acceleration, both directions: 10 deg. s-2
Receiver noise figure (LNA + others): 3.4 dB (LNA)
Losses: 2.3 dB (T-R-switch), 0.4 dB (waveguide, receive path), 0.9 dB (waveguide and circulator, transmit path)
Sensitivity at 5 km, PRF = 5 kHz, 200 ns, NFFT = 256, averaging time 0.1 s: -44 dBZ

Manufacturer: Metek GmbH