In this paper, we will introduce a cocentered orthogonal loop and dipole antenna (COLD) to a borehole radar system. With the cocentered orthogonal loop and dipole antenna, we could obtain additional information on polarization state of arrival waves in the borehole radar using * optical modulators. We set the proposed antenna in a borehole actually, and made electromagnetic waves with known pol...

MIMO radar for imaging is a quite new and promising research field with a big potential for various applications. Three different imaging radars based on the MIMO principle are currently developed at Fraunhofer FHR. This paper describes the ground based X-band MIMO radar MIRA-CLE X. This radar consists of 16 transmit and 14 receive antennas which are arranged in a special way to synthesize a fu...

Modern spaceborne radar scatterometers such as the NASA Scatterometer (NSCAT) and SeaWinds radar instruments require precise determination of the normalized backscattered radar cross section within a few tenth of a decibel in order to achieve the desired wind velocity and direction measurement accuracy of 2 m/s and 20 degrees respectively. This high level of precision requires a priori prelaunc...

Recent research has suggested that the geostatistical structure of ground-penetrating radar data may be representative of the spatial structure of hydraulic properties. However, radar images of the subsurface can change drastically with application of signal processing or by changing the signal frequency. We perform geostatistical analyses of surface radar reflection profiles in order to invest...

In the last years, the Synthetic Aperture Radar (SAR) systems evolution migrates toward the use of multi-channel systems based on Digital Beam Forming (DBF) techniques [1]. This tendendy allows fulfilling stringent SAR requirements, providing high spatial resolution within a wide swath. Moreover, the combination of DBF techniques with parabolic reflector antennas merges both flexibility and hig...

The on-orbit alignment of the antenna beams of both the X-band and C-band radar systems during operations of the shuttle radar topography mission/X-band synthetic aperture radar (SRTM/X-SAR) was a key requirement for achieving best interferometric performance. In this paper, we consider the X-SAR antenna beam alignment in azimuth. For a single-pass cross-track SAR interferometer, we establish t...

Through intensive study, it has been explored that multipleinput single-output (MISO) antenna systems have the potential to dramatically improve the performance of communication systems over single antenna systems. With the idea of implementing WiMAX MISO Communication Technology for overcoming the challenges offered by hostile channel and environmental effects, it leads the Technocrats to util...

We investigate the feasibility of calibrating HF radar systems using HF backscatter from ships along with Automatic Identification System (AIS) broadcasts. We obtained data from 4 SeaSondes, located in the vicinity of the Santa Barbara Channel, with coincident AIS data recorded over 70 days. Using the ship position information from AIS, we identify corresponding ship echoes in SeaSonde HF radar...

Polarization properties of radar waves that are scattered from atmospheric objects are of great interest in meteorological studies. However, polarimetric radar measurements are often not sufficiently accurate for retrieving physical properties of targets. To compensate for errors, radar polarimetric calibration is applied. Typical calibrations are performed based on measurements of point target...

The influence of a surface-active substance (SAS) film on the Doppler spectrum width at small incidence angles is theoretically investigated for the first time for microwave radars with narrow-beam and knife-beam antenna patterns. It is shown that the requirements specified for the antenna system depend on the radar motion velocity. A narrow-beam antenna pattern should be used to detect slicks ...