Javier Bará

Learn More
This paper is concerned with the radiometric sensitivity computation of an aperture synthesis interferometric radiometer devoted to earth observation. The impact of system parameters and the use of simultaneous redundant measurements are analyzed. The Interferometric Radiometer Uncertainty Principle is presented; it quantifies the relationship between(More)
The spatial resolution of current space-borne Earth observation radiometers is limited by the physical antenna aperture. This is especially critical at -band, which exhibits high sensitivity to soil moisture and sea surface salinity. Interferometric radiometers (InR’s) are currently being studied by several space agencies as a feasible alternative to(More)
Current spaceborne radiometers do not achieve the required spatial resolution demanded by the scientific community due to antenna-size technological limitations. In recent years, several space agencies have been studying aperture synthesis interferometric radiometers as a way of overcoming these limitations, which are more evident at low microwave(More)
The correlation between the visibility samples’ noise of an aperture synthesis radiometer are required for the computation of the recovered temperature noise of a given pixel and of the improvement introduced by baseline redundance. A general expression for this correlation and noise examples for a linear array are presented.
To estimate the probability distributions of power fades, we consider two basic types of disturbance in electromagnetic wave propagation through atmospheric turbulence: wave-front intensity fluctuations and wave-front distortion. We assess the reduction in the cumulative probability of losses caused by these two effects through spatial diversity by using a(More)
Assuming a symmetric transmit filter for which the receive filter is to be optimised, we expect the symmetric receive fdter coefficients (eqn. 12) to be practically the same as those for the nonsymmetric filters (eqn. 5). This is verified by a set of examples with different receive filter lengths NR and transmit filter excess bandwidth values a. An AWGN(More)
Passive imaging using mm-waves offers very significant advantages in scientific and military surveillance. However, the relatively long wavelengths mean that for the resolutions that are sought, the input aperture of the imager needs to be quite large, typically in excess of one meter. Deployment of conventional dish antennas of these dimensions on aircraft(More)