Microwave Imaging Radiometer with Aperture Synthesis
Encyclopedia
Microwave Imaging Radiometer with Aperture Synthesis (MIRAS) is the major instrument on the Soil Moisture and Ocean Salinity satellite
(SMOS). MIRAS is a planar antenna composed of a central body (the so-called hub) and three telescoping, deployable arms, in total 69 receivers on the Unit. Each receiver is composed of one LICEF module, which detects radiation in the microwave
L-band, both in horizontal and vertical polarizations. The aperture on the LICEF detectors, planar in arrangement on MIRAS, point directly toward the Earth's surface as the satellite orbits. The arrangement and orientation of MIRAS makes the instrument a 2-D interferometric radiometer
.
The MIRAS instrument's prime contractor was EADS CASA Espacio, manufacturing the payload of SMOS under ESA's contract.
element, with 2 pairs of probes for orthogonal linear polarisations, feeding two receiver channels in a compact lightweight package behind the antenna. It picks up thermal radiation
emitted by the Earth near 1.4 GHz in the microwave
L-band, amplifies it 100 dB
, and digitises it with 1-bit quantisation. MIER
is the subcontractor.
Soil Moisture and Ocean Salinity satellite
The Soil Moisture and Ocean Salinity Satellite is a part of ESA's Living Planet Programme intended to provide new insights into Earth's water cycle and climate...
(SMOS). MIRAS is a planar antenna composed of a central body (the so-called hub) and three telescoping, deployable arms, in total 69 receivers on the Unit. Each receiver is composed of one LICEF module, which detects radiation in the microwave
Microwave
Microwaves, a subset of radio waves, have wavelengths ranging from as long as one meter to as short as one millimeter, or equivalently, with frequencies between 300 MHz and 300 GHz. This broad definition includes both UHF and EHF , and various sources use different boundaries...
L-band, both in horizontal and vertical polarizations. The aperture on the LICEF detectors, planar in arrangement on MIRAS, point directly toward the Earth's surface as the satellite orbits. The arrangement and orientation of MIRAS makes the instrument a 2-D interferometric radiometer
Radiometer
A radiometer is a device for measuring the radiant flux of electromagnetic radiation. Generally, the term radiometer denotes an infrared radiation detector, yet it also includes detectors operating on any electromagnetic wavelength....
.
The MIRAS instrument's prime contractor was EADS CASA Espacio, manufacturing the payload of SMOS under ESA's contract.
LICEF
The LICEF detector is composed of a round patch antennaPatch antenna
A patch antenna is a type of radio antenna with a low profile, which can be mounted on a flat surface. It consists of a flat rectangular sheet or "patch" of metal, mounted over a larger sheet of metal called a ground plane. The assembly is usually contained inside a plastic radome, which...
element, with 2 pairs of probes for orthogonal linear polarisations, feeding two receiver channels in a compact lightweight package behind the antenna. It picks up thermal radiation
Thermal radiation
Thermal radiation is electromagnetic radiation generated by the thermal motion of charged particles in matter. All matter with a temperature greater than absolute zero emits thermal radiation....
emitted by the Earth near 1.4 GHz in the microwave
Microwave
Microwaves, a subset of radio waves, have wavelengths ranging from as long as one meter to as short as one millimeter, or equivalently, with frequencies between 300 MHz and 300 GHz. This broad definition includes both UHF and EHF , and various sources use different boundaries...
L-band, amplifies it 100 dB
Decibel
The decibel is a logarithmic unit that indicates the ratio of a physical quantity relative to a specified or implied reference level. A ratio in decibels is ten times the logarithm to base 10 of the ratio of two power quantities...
, and digitises it with 1-bit quantisation. MIER
Mier
Mier might refer to one of the following:* Mier, Asturias, a small principality in northern Spain* Ciudad Mier, a city and municipality in northern Mexico* Mier Local Municipality, a municipality in South Africa's Northern Cape province...
is the subcontractor.