Development and characterization of fully polarimetric noise injection radiometer for MIRAS

Abstract

An L-band noise injection radiometer (NIR) has been designed and implemented by Helsinki University of Technology Laboratory of Space Technology for the SMOS (Soil Moisture and Ocean Salinity) mission of ESA [1]. The work is performed as a part of ESA's MIRAS Demonstrator Pilot Project-2 (MDPP-2) under a subcontract for EADS-CASA. Other partners in the MDPP-2 NIR project are Toikka Engineering Ltd. and Ylinen Electronics Ltd.NIR will work as a part of the MIRAS (Microwave Imaging Radiometer Using Aperture Synthesis) instrument. Its main purpose is (1) to provide precise measurement of the average brightness temperature scene for absolute calibration of the MIRAS image map and (2) to measure the noise temperature level of the internal active calibration source for individual receiver calibration. The performance of NIR is a decisive factor of the MIRAS performance.The challenge in the implemented, so-called blind correlation, method is the fact that there is additional noise in the correlated signal due to using the noise injection method. The main objective of this paper is to demonstrate the feasibility of this technique.

Detection of a Sea Surface Salinity Gradient Using Data Sets of Airborne Synthetic Aperture Radiometer HUT-2-D and a GNSS-R Instrument

“…In the frame of this thesis different calibration, reconstruction and rectification algorithms were studied, adjusted, and implemented for the air- Besides the two publications given above the author has written or con-tributed to several publications in this context: [80], [148], [149], [150], [151], [152], [153], [154].…”

Research Activity on Synthetic Aperture Radiometry in CSSAR/CAS

“…To ensure the success of the space mission, several universities participated in the research under the support and coordination of ESA. UPC has done lots of work on imaging algorithm research, system performance analysis (such as spatial resolution, radiometric resolution, etc), and end to end system simulation [10]∼ [13]; HUT has developed a NIR for calibration, and a U-shape airborne demonstrator [14] [15]. All of these detailed research work drive the development of synthetic aperture radiometry effectively.…”

Two-dimensional interferometric radiometry: image validation using celestial objects

“…the integrated brightness temperature of the scene will be measured using the Noise Injection Radiometer (NIR) [5]. This is expected to give substantial improvement for the absolute calibration of the retrieved brightness temperature scene; a noise injection radiometer has significantly higher inherent gain and offset stability than the total power LICEF-receivers.…”